1.
The diagram shows a summary of some of the steps in aerobic respiration. Pyruvate L in k r e a c tio n
N A D N A D H + H
+
electron-transport chain
A c e ty l C o e n z y m e A
K re b s c y c le
(a)
N A D N A D H + H
+
electron-transport chain
State precisely precisely where Krebs cycle takes place within a cell. cell. .......................................................................... ................................................................................................................ .......................................................... .................... (1)
(b)
Name the the process process that results results in the produc production tion of of ATP from ADP by the electro electronntransport chain. .......................................................................... ................................................................................................................ .......................................................... .................... (1)
(c)
With referen reference ce to the diagram diagram,, explain explain why why Krebs Krebs cycle cycle can only take place place when when oxygen oxygen is available. .......................................................................... ................................................................................................................ .......................................................... .................... .......................................................................... ................................................................................................................ .......................................................... .................... .......................................................................... ................................................................................................................ .......................................................... .................... .......................................................................... ................................................................................................................ .......................................................... .................... (2) (Total 4 marks)
1
2.
The diagram below shows a summary of glycolysis and two alternative pathways that may follow this process in anaerobic conditions.
G lu c o s e
G ly c o ly s is P a th w a y A T ak e s pl ace in e x e r c i s in g m u s c l e s
L a c t ic a c id
(a) (a)
X
P a th w a y B T a k e s p l a c e in y e a s t c e l ls W a s te p r o d u c ts
Subs Substa tanc ncee X is the final product of glycolysis. Name this substance. ……………………………………………….……………………………………… (1)
(b)
In glycolysis glycolysis,, NAD NAD is converted converted to its its reduce reduced d form form (NADH (NADH + H+). Describe how NAD is regenerated in pathway A. ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… (2)
(c)
Name the waste products products of pathway pathway B. ……………………………………………….……………………………………… (1)
(d)
Describe Describe the role of reduced reduced NAD (NADH + H +) when respiration takes place in aerobic conditions. ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… ……………………………………………….……………………………………… (3) (Total 7 marks)
3.
Give an account of the stages of respiration that take place in the mitochondrion, stating the location of each stage.
(Allow three lined pages) (Total 10 marks)
4.
Give an account of the anaerobic respiration of glucose by yeast.
(Allow three lined pages) (Total 10 marks)
3
5.
The flow chart below illustrates some of the stages that occur in glycolysis.
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6
c
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(a)
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a
State the net net gain gain in ATP from from one molecu molecule le of glucose glucose in glycolysis glycolysis.. .......................................................................... ................................................................................................................ .................................................................. ............................ (1)
(b)
Explain Explain why the yield yield of of ATP from from the the respiratio respiration n of one molecu molecule le of glucose glucose when when oxygen is present is present is more than the yield of ATP from the respiration of one molecule of glucose under anaerobic conditions. .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ (5) (Total 6 marks)
6.
The diagram below shows part of a metabolic pathway which occurs in mitochondria.
c
-i sa
c
o
n
i t a
t e
i s o
c
i t r a
t e
+
(a)
N
o
A
D
x
+
a
l o
s u
N
A
D
H
Explai Explain n what what is meant meant by the term term metabolic pathway. .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ (2)
5
(b)
+
Suggest Suggest what happens happens to the NADH + H formed during the conversion of isocitrate to oxalosuccinate. .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ (2)
(c) (c)
The The conv conver ersi sion on of cis-aconitate to isocitrate is catalysed by the enzyme aconitase. The leaves of some plants contain a substance called fluoroacetate. If this is eaten by animals, it is absorbed into their cells where it is converted to fluorocitrate. Fluorocitrate i s an inhibitor of the enzyme aconitase. Suggest what effect fluorocitrate would have on the production of ATP by mitochondria. Give an explanation for your answer. .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ .......................................................................... ................................................................................................................ .................................................................. ............................ (4) (Total 8 marks)
7.
The diagram below shows a section through the membranes of a mitochondrion.
I n
O C
r i s t a
n
u
e r
t e
m
r
e I n t e r m s p a c e
S p
m
t a l k e d a r t i c l e
e
s
With reference to the structures labelled on the diagram, describe the role of the mitochondrial membranes in the production of ATP. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. (Total 5 marks)
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8.
In an investigation, small samples of tissue were removed from the leg muscles of international athletes of the same age and sex. The athletes included sprinters (100 m), middle distance runners (800 m) and long distance runners. SDH is an enzyme involved in the reactions of the Krebs cycle. LDH is an enzyme that catalyses the conversion of pyruvate to lactate. The results of the analysis of the muscles are shown in the table below. Athletes
Mean percentage of slow twitch fibres
Mean SDH activity /arbitrary units
Mean LDH activity /arbitrary units
100 m sprinters
24
1.70
1.60
800 m runners
52
2.00
1.10
Long distance runners
70
2.25
1.00
(a)
Explain Explain why successfu successfull sprinters sprinters usually usually have have a low low percentag percentagee of slow twitch twitch fibres in their leg muscles. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (2)
(b)
Explain Explain the relationsh relationships ips between between the the mean mean activity activity of of SDH and LDH LDH in the leg muscles muscles and the distances run by the athletes. (i)
SDH ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2)
(ii)
LDH ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2)
(c)
Describe Describe the role of of the electro electron n transpor transportt chain of of mitochond mitochondria ria in the the synthesis synthesis of ATP. ATP. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (4)
(d)
Explain Explain the fate fate of lactate lactate produced produced by the activity activity of of LDH in athletes athletes such as sprinter sprinters. s. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (2) (Total 12 marks)
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9.
An investigation was carried out into the effect of cyanide on the respiration of yeast cells. Cyanide is an electron transport inhibitor. It binds irreversibly with one of the electron carriers. The yeast cells were mixed with a buffer solution which had ADP, phosphate ions and glucose dissolved in it. This suspension was incubated for 30 minutes and during this time the oxygen content of the solution was monitored using an oxygen probe. The experiment was then repeated but cyanide was added to the suspension after 5 minutes of incubation. The results obtained are shown in the graph below.
1
0
O x y g e n c o n t e n t t h e s u s p e n s8 i o n / a r b i t r a r y u n i t s 6
o
f
C
y
N
o
a
n
i d
e
4 2 0 0
5 T
(a)
1 i m
e
0 o
2 f
i n
15
53
0
c u
b
a t i o
c y 2
a
n
0 n
/
m
State precisely precisely where the electron electron transport transport chain is found. found. .......................................................................... ................................................................................................................ ............................................................ ...................... (1)
(b)
Explain why the the oxygen oxygen content content of of the suspension did not change change after the cyanide was added. .......................................................................... ................................................................................................................ ............................................................ ...................... .......................................................................... ................................................................................................................ ............................................................ ...................... .......................................................................... ................................................................................................................ ............................................................ ...................... .......................................................................... ................................................................................................................ ............................................................ ...................... (2)
(c)
Suggest Suggest why the oxygen oxygen conten contentt of the the suspensio suspension n of cells cells without without cyanid cyanidee did not not reach reach zero. .......................................................................... ................................................................................................................ ............................................................ ...................... .......................................................................... ................................................................................................................ ............................................................ ...................... .......................................................................... ................................................................................................................ ............................................................ ...................... .......................................................................... ................................................................................................................ ............................................................ ...................... (2) (Total 5 marks)
11
10.
The flow diagram below shows some of the steps involved in glycolysis and the Krebs cycle. Some ATP is made directly. Hydrogen is also released and this can result in the production of more ATP.
(a)
Describe Describe how the hydrog hydrogen en released released during during glycolysis glycolysis and and the Krebs cycle cycle results results in in the production of ATP. .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... .......................................................................... ................................................................................................................ ............................................................. ....................... (4)
(b)
Using the informa information tion in the the diagram, diagram, state state the the number number of ATP ATP molecules molecules produc produced ed from from one triose phosphate molecule. .......................................................................... ................................................................................................................ ............................................................. ....................... (1)
(c)
As well well as carbohy carbohydrates drates,, triglyceri triglycerides des can can be respire respired. d. The first first step is is to break break down down each triglyceride molecule into glycerol and three fatty acids. Each fatty acid is broken down into acetyl CoA molecules. The acetyl CoA molecules then enter the Krebs cycle. (i)
Using the inform information ation in the the diagram diagram,, state state the the number number of ATP ATP molecules molecules produced produced from one acetyl CoA molecule. ......................................................................... ............................................................................................................... ....................................................... ................. (1)
13
(ii)
Suggest Suggest why fatty fatty acids acids can only only be respired respired under under aerobic aerobic conditions. conditions. ......................................................................... ............................................................................................................... ....................................................... ................. ......................................................................... ............................................................................................................... ....................................................... ................. ......................................................................... ............................................................................................................... ....................................................... ................. ......................................................................... ............................................................................................................... ....................................................... ................. ......................................................................... ............................................................................................................... ....................................................... ................. ......................................................................... ............................................................................................................... ....................................................... ................. (3) (Total 9 marks)
11.
The diagram below summarises some of the stages of a metabolic pathway responsible for generating ATP in mitochondria.
r e d u c e d h y d r o g e c a r r i e r
2 H ( f r o m r e d u c
2 e
d
N
A
D
(i)
–
x y
i d i s e d t o c h r o
m
e
e
2
)
o x i d i s e d h y d r o g e n c a r r i e r
(a)
o c
n
2
+
r e d u c e d c y t o c h r o
m
–
e
e
H
Name the metabolic pathway shown in this diagram.
......................................................................... ............................................................................................................... .................................................. ............ (1)
(ii)
Name the the type type of enzyme enzyme involved involved in this this pathway pathway and and explain explain its role. role. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2)
(b)
Explain Explain what what happens happens to the electrons electrons releas released ed at the end end of this pathwa pathway. y. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (2) (Total 5 marks)
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12.
In oxidative phosphorylation, ATP is formed when electrons pass down the electron transport chain from one component to the next. ATP is synthesised at three sites. The order of some components in the electron transport chain and the three sites of ATP synthesis are shown in the diagram below.
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(a)
+
The oxidation oxidation of one molecule molecule of reduced reduced NAD (NADH + H ) yields three molecules of ATP. Using the information given in the diagram above and your knowledge of mitochondria and oxidative phosphorylation, explain how the three molecules of ATP are made. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (4)
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(b)
The diagra diagram m below below shows shows some some of the stages stages that occur occur in in the Krebs cycle. cycle.
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1
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D
Using the information given in both diagrams, explain why the oxidation of one molecule of succinate to oxaloacetate yields only five molecules of ATP. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (3)
(c)
State where in the cell the following following processes processes take place. place. Glycolysis.............................................................. Glycolysis........................ .............................................................................. ..................................................... ............. Conversion of pyruvate to acetyl coenzyme A.......................................................... Krebs cycle................................ cycle...................................................................... .............................................................................. ........................................... ... (3) (Total 10 marks)
13.
The diagram below shows some of the stages in aerobic respiration.
G 2
l u
H p
2
y
r u
H
c a r b o n m p o u n
c o
A
T
o
s e P A
A
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X
a c e t y
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(a)
(i)
c a r b o m p o u
H
c o
c a r b o n m p o u n
H
d
Name substance X:
................................................................................................................. ............................................... ....... X ......................................................................... (1)
(ii) (ii)
Name Name stag stages es A and B: A ......................................................................... ................................................................................................................. ............................................... ....... B ..................................................................... ............................................................................................................. ................................................... ........... (1)
19
(b)
Explain Explain what what happens happens to the the hydroge hydrogen n that that is produced produced during during stage stage B. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (4)
(c)
Explain Explain how how ATP ATP is is able able to supply supply energy energy for biological biological processes processes.. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (1) (Total 7 marks)
14.
Give an account of anaerobic respiration of glucose in a mammalian muscle cell.
(Allow two lined pages). (Total 10 marks)
15.
The table below refers to three major stages of aerobic respiration and the products of each stage. Complete the table by inserting the part of the cell in which the stage occurs and two products in the blank spaces. Stage
Part of cell in which it occurs
Two products
Glycolysis
Krebs cycle
Matrix of mitochondrion
Electron transport chain
ATP and water (Total 4 marks)
(a)
16.
G
The diagra diagram m below below shows shows an outline outline of anaero anaerobic bic respir respiration ation in a yeast cell.
l u
c
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s e
2
P
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a
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t e
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(i) (i)
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b
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Name Name subs substa tanc ncee X. ......................................................................... ............................................................................................................... .................................................. ............ (1)
21
(ii)
Explain Explain why why it is necessary necessary for the the cell to convert convert ethanal ethanal to ethanol. ethanol. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2)
(b)
A student student carried carried out out an investi investigation gation into the the effect effect of glucose glucose and sucrose sucrose on the rate of of respiration of yeast cells. Triphenyl tetrazolium chloride (TTC) is an artificial hydrogen acceptor, which is colourless in the oxidised form and red when reduced. A colorimeter is an instrument used to measure the percentage of light transmitted through a liquid. In this investigation, when the TTC is fully oxidised 100% of the light is transmitted through the liquid. The darker the red colour of the TTC solution becomes, the lower the percentage of light transmitted. Yeast cells were suspended in 0.5% glucose solution. The student set up a tube containing 10 cm3 of this suspension and 1 cm3 of TTC solution. The tube was covered and placed in a water bath for 20 minutes. During this time, the percentage of li ght transmitted through the solution was measured at two-minute intervals. The experiment was repeated using yeast cells suspended in 0.5% sucrose solution. The results of the investigation are shown in the graph below.
1
0
8
0
0
P e r c e n t a g e o f l i g 6h 0t t r a n s m i t t e d ( % ) 4
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(i)
Describe Describe the the rate rate of of respira respiration tion of yeast yeast in the the glucose glucose solution solution during the 20 20 minutes of this investigation. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (3)
(ii)
State one way in which the rate of respiration of yeast in the sucrose solution differs from the rate in the glucose solution. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (1)
(iii)
Explain Explain why the tubes tubes were were covered covered during during this this investig investigation. ation. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2)
(iv)
Explain Explain why why the student student placed placed the the tubes tubes in a water bath. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2) (Total 11 marks)
17.
The diagram below shows a simple respirometer used to investigate gas exchange in germinating seeds.
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1
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C
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25
(a)
Suggest Suggest a function function for each of the following. following. (i) (i)
The The syri syring ngee ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (1)
(ii)
The potassium potassium hydroxide hydroxide solution solution ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (1)
(b)
Suggest Suggest why immersing immersing the respiromete respirometerr in a water water bath bath helps helps to ensure ensure that the the results results are reliable. .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... .......................................................................... ................................................................................................................ ........................................................... ..................... (2)
(c)
In an invest investigatio igation n to measure measure the rate rate of oxygen oxygen uptake uptake by the the seeds, seeds, the coloured coloured liquid liquid moved 12 mm up the right hand side of the capillary tube in 15 minutes. The cross2
sectional area of the capillary tube is 0.19 mm . Calculate the volume of oxygen taken up per minute by the seeds. Show your working.
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Answer = ................................... mm oxygen min
(3) (Total 7 marks)
18.
(a) The diagra diagram m below below shows shows some some of the stages stages of anaerob anaerobic ic respirat respiration ion in a muscle muscle cell.
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Name Name subs substa tanc ncee A. ......................................................................... ............................................................................................................... .................................................. ............ (1)
(ii)
State which of the stages shown in the diagram: diagram: Uses ATP .......................................................................... .......................................................................................................... ................................ Produces ATP ....................................................................... ................................................................................................... ............................ (2)
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(b)
The Krebs Krebs cycle occurs occurs during during aerobi aerobicc respiratio respiration n and is an example example of a metabolic metabolic pathway. (i)
Explain Explain why the Krebs cycle is described described as a metabol metabolic ic pathway. pathway. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (1)
(ii)
State precisely precisely where in the cell the Krebs cycle occurs. occurs. ......................................................................... ............................................................................................................... .................................................. ............ (1)
(c)
The diagra diagram m below below shows shows some some of the the stages stages that occur in the the Krebs Krebs cycle. cycle.
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Oxidoreductase enzymes are involved in some of the reactions in the Krebs cycle. Using the letters A to F and the information given in the diagram, list all the stages that involve an oxidoreductase enzyme. .......................................................................... ................................................................................................................ ........................................................... ..................... (1) (Total 6 marks)
19.
Isolated mitochondria in a solution containing inorganic phosphate and an electron donor can be used to study respiration. An electrode is used to record changes in oxygen concentration while mitochondria respire. The graph below shows c hanges in oxygen concentration for some isolated mitochondria.
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Describe and explai lain the the trends shown on the graph aph above.
......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (3)
(ii)
Name an an electron electron donor used in the electron electron transpo transport rt chain chain in mitochondr mitochondria. ia. ......................................................................... ............................................................................................................... .................................................. ............ (1)
(iii)
State the the location location of the electron electron transport transport chain chain in mitochondr mitochondria. ia. ......................................................................... ............................................................................................................... .................................................. ............ (1)
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(iv)
Describe Describe how how ATP is synthesise synthesised d in the the electron electron transpo transport rt chain. chain. ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (3)
(b)
ATP is used to provide provide an immediate immediate supply supply of energy energy for biological biological process processes. es. Describe the role of ATP in the following processes. (i) (i)
Nerv Nervee impu impuls lsee transmission ....................................................................... ............................................................................................................. ......................................... ... ............... ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2)
(ii)
Hyperpolar Hyperpolarisatio isation n of rod cells in the retina ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ ......................................................................... ............................................................................................................... .................................................. ............ (2) (Total 12 marks)
