Photosynthesis – light energy from sun into chemical potential potential energy
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Releases oxygen from water Autotrophs – use light energy or chemical energy e nergy and inorganic molecules (co2 + water) to synthesise complex organic molecules Chemoautotroph – synthesise organic molecules using energy from exergenoic exergenoic reactions(e.g. nitrifying bacteria) Photoautotroph’s – Organisms that can photosynthesise – Plants !acteria Protoctists Heterotrophs – ingest and digest complex organic molecules releasing chemical potential energy stored in them. 6CO2 + 6H20 (+LIGHT ENEG!" C6H#2O6 + 602 " " " " " " " Photosynthesis Other way around is respiration
Photosynthesis happens in $h%orop%asts.
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#tructure of chloroplasts$ • •
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%isc shaped & 2'#0 um long %ouble membrane &nter membrane space #0'20nm wide Outer is permea%e to sma%% ions Inner has transport proteins) &nner folded into %ame%%ae which are sta$*e up to form a ,ranum !etween grana are inter,rana% %ame%%ae -troma – 'uid lled matrix – reactions of %i,ht inepenent stage occur here. ecessary en*ymes are located here. #tarch grains and oil droplets also in stroma and % and pro,aryote type ribosomes too Grana – stac,s of 'attened thyla,oid membranes. -ight absorption and P synthesis in light dependent stage happen here. daptations &nner membrane can $ontro% entry.e/it of substances between cytoplasm and
stroma •
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/rana has 011 stac,s of thyla,oid membranes so %ar,e sura$e area or photosyntheti$ pi,ments electron carriers and P synthase en*ymes Photosynthetic pigments arran,e in photo systems Proteins in the grana hold the photo systems in place pl ace #troma has en*ymes to catalyse reactions of light independent /rana surrounded by stroma so products from dependent stage which are needed in independent stage can pass into stroma easily hloroplasts ha3e % and ribosomes so they can easily ma,e the necessary proteins
Photosynthetic pigments • •
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hey tried to capture as as much light as possible re found in thyla,oid membranes arranged in funnel shaped structures – photo systems hlorophyll is a mixture of pigments – has a 1, atom a %on, phyto% an a porphyrin group
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-ight hits chlorophyll a causing pair of electrons ele ctrons to be exited wo wo forms of chlorophyll chlorophyll one in P451 and other in P611 – both both are yellow7green !oth found at centre of photo systems and are ,nown as primary pigment reaction centres P451 – P#&&" absorbs light at 451nm P611 – P#& – absorbs light at 611nm Ch%orophy%%% a asors %ue %i,ht at 340nm Ch%orophy% Ch%orophy%%% asors %i,ht aroun 400nm an 630nm appears Ch%orophy% %ue.,reen
ccessory pigments
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Carotenois re5e$t ye%%o an oran,e %i,ht an asor %ue %i,ht %on8t contain porphyrin and aren8t in3ol3ed directly in light dependent bsorb light which isn8t absorbed well by chlorophyll and pass the energy associated to chlorophyll at base of photo system arotene(orange) and xanthophylls(yellow) are main arotenoids pigments &n photo system main pigment is at the bottom where the light hits he accessory pigment are are located around photo system system and absorb light that the main photosynthetic pigment can8t absorb he absorbed light energy passed passed down to the primary pigment reaction reaction centre hlorophyll is located there and energy is supplied there to excite electrons
-ight dependent stage • •
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a,es a,es place on thyla,oid thyla,oid membrane P#& is usually on the intergranal lamellae and P#&& occurs almost all the time on the granal lamella hese pigments trap light energy so it can be con3erted to chemical energy then P P#&& has an en*yme that can split water into 9+ ions electrons and oxygen 2h20 3h+ + 3e' + O2 Oxygen produced is used for aerobic respiration and some di:uses out through stomata #plitting of water forms 9+ ions used in chemiosmosis to produce P. P. 9+ accepted by coen*yme %P which becomes reduced %P9. %P9 used in light independent stage to reduce co2 and produce organic molecules. ;ater is also a source of electrons ele ctrons to replaces ones lost by oxidised chlorophyll
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Photophosphorylation • •
-ight tra3els in particles called photons ;hen a photon hits a chlorophyll molecule the energy of the photon is transferred to two electrons and they become excited. he electrons are captured by electron acceptors and passed along a series of electron carries embedded in the thyla,oid membranes.
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oined forming P P.. ?inetic energy from proton 'ow is con3erted to energy in P molecules used in light independent stage of photosynthesis. =low of protons is called chemiosmosis @a,ing of P using light energy is called Photophosphorylation. wo wo types – yclic and on"yclic on"yclic
yclic Photophosphorylation •
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Ases P#&.
on cyclic Photophosphorylation • • •
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&n3ol3es P#& and P#&& -ight hits P#&& excites electrons that lea3e chlorophyll molecule from PPR oin %P to form %P9
-ight independent stage al3in ycle • • •
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a,es a,es place in stroma stroma Products of light dependent stage are reBuired O2 from air di:uses into leaf through stomata (bottom of leaf). %i:uses throughout air spaces in spongy mesophyll and reaches palisade mesophyll layer. layer. hen di:uses through thin cellulose walls the cell surface membrane cytoplasm and then the chloroplast en3elope into the stroma. &n stroma O2 combined with C carbon Ru!P (co2 accepter). Reaction Reaction catalysed by rubisco. RA!P becomes become s carboxlyated. =orms D carbon glycerate D phosphate (/P)O2 is now xed /P is reduced and phosphorylated to triose phosphate (P) P and %P9 from light dependent are used in this process
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C out of 4 P are recycled by phosphorylation using P from light dependant to D molecules of Ru!P
9ow are they usedE
-ome GP $an e use to ma*e amino a$is an atty a$is Pairs o TP mo%e$u%es $omine to orm he/ose su,ars e),) ,%u$ose an ru$tose -ome ,%u$ose $an e isomerise to orm he/ose su,ar G%u$ose an ru$tose $an e $omine to orm isa$$harie su$rose to e trans%o$ate in ph%oem sie7e tues He/ose su,ars $an e po%ymerise into other $ars su$h as $e%%u%ose an star$h TP $an e $on7erte to ,%y$ero% an may e $omine ith atty a$i to orm GP to ma*e %ipi
-imiting factors • •
-ight intensity O2 conc emperature emperature are all limiting factors oo oo high temperature will cause proteins proteins to be denatured
<:ect of light intensity • •
auses stomata to open so O2 can enter lea3es -ight is trapped by chlorophyll where it excites electrons -p%its ater mo%e$u%es to prou$e protons
<:ect of temperature • •
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!etween 1"2CO Photosynthesis doubles for each 01 o rise bo3e 2C it le3els o: then falls because en*ymes wor, less eFciently and oxygen successfully competes for acti3e site of rubisco stopping O2 from binding auses loss of water from stomata ma,ing stress response to close the stomata limiting O2 a3ailable
@easuring photosynthesis •
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@easure upta,e of substrates or appearance of products per second7minute Golume of oxygen produced Rate of O2 upta,e Rate of increase in dry mass of plants pl ants Asually measured by oxygen produced "-imitations are that some oxygen produced will be used for respiration by the plant "here maybe be some dissol3ed nitrogen in the gas collected. Photosynthometer7udus microburette air tight so no bubbles in capillary tubing /as collected at 'are at end of rube
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/as buble can be meo3ed into the part of the capillary tube against the scale and its length can be measured Golume of gas collected H length of buble x pi R I2 ompare rates by using the length of gas bubble e3ol3ed per unit time time gi3en diameter is constant 9ow to measure$ "=ill "=ill apparatus with tap water. water. Remo3e plunger from synrige and gentle stream of tap water into the syringe until whole barrel and plastic tube are full of water "Replace synringe plunger and gently push water out of 'ared end of capillary tubing until plunger is nearly at the end of the syringe and no air bubbles. "ut well illuminated
-ight intensity •
- H 07d2 &t alters light dependant reaction 1ore %i,ht 8 more e/$itation o e%e$trons 1ore e%e$trons e/$ite 8 ,reater phosphory%ation so more ATP an NA9PH prou$e ATP an NA9PH use in %i,ht inepenent as sour$e o hyro,en an ener,y to reu$e GP to TP) ATP use to phosphory%ate 4.6 mo%e$u%es o TP to re,enerate :;P I there’s no %i,ht then GP $an’t e $han,e to TP so GP i%% a$$umu%ate)
Loer amount o u;P reu$in, CO2
In$rease amount 8 more CO2 photosyntehsis photosyntehsis Conse?uent%y ATP an NA9PH rom %i,ht epenant is aste eu$es o7era%% rate o photosynthesis @ery hi,h temp $an enature In$rease temp $auses an in$rease in ater %oss rom %ea7es y transpiration) Can %ea to $%osure o stomata an reu$tion in photosynthesis photosynthesis rate
&n this Buestion one mar, is a3ailable for the Buality of use and organisation of scientic terms. here are a number of organic organic molecules in cells whose role is to transfer hydrogen atoms from one compound to another.
role of these molecules within a palisade mesophyll cell
;hen plants are grown in glasshouses during autumn and winter when the natural light intensities are low it is i s important that temperatures are ,ept relati3ely low. ;ith referenceto respiration and photosynthesis explain explain why it is essential to do this. .........................................................................................................................
/o through diagram of hloroplast
-earn about @esophyll cells
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/ood communication system$
Co7er ho%e oy Ce%% $ommuni$ation -pe$i<$ $ommuni$ation api $ommuni$ation -hort an %on, term responses
ell signalling euronal system – inter$onne$te netor* o neurons that si,na% to ea$h other a$ross synapse Bun$tions) Are ?ui$* an $an ena%e rapi responses to stimu%i $han,in, ?ui$*%y Hormona% system & uses %oo to transport it si,na%) Ce%%s in an eno$rine or,an re%ease the hormone into the %oo) Carrie a%% o7er oy ut re$o,nise y spe$i<$ tar,et $e%%s) Lon, term 9omeostasis$ •
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@aintenance of internal en3ironment in a constant stage despite external changes. his that ha3e to be ,ept ,ept constant$ emp !lood salt conc !lood glucose conc water potential of blood blood bl ood pressure co2 conc
egati3e feedbac, • • •
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ny change to internal en3ironment must be detected hange must be signalled to other cells @ust be a response that re3erses the change Ne,ati7e eea$* eea$* Pro$ess that rin,s aout a re7ersa% o any $han,e in $onitions) Ensures that an optimum steay state $an e maintaine as the interna% en7ironment is returne to its ori,ina% set o $onitions ater any $han,e) #timulusJReceptorJommunication #timulusJReceptorJ ommunication Pathway (cell signalling) J <:ector J Response #ensory receptors such as temperature receptors glucose conc receptors are internal and monitor conditions inside the boy &f they detect a change they will send a message communication system such as the ner3ous system or the hormonal system acts by signalling between cells. Ases to transmit message from receptor cells to e:ectors cells he message may or may not pass pass through a coordination coordination centre such as the brain <:ector cells such as li3er or muscle cells will bring about the response and re3erse the change
Positi3e feedbac,
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&ncreases the original change and usually harmful. E/amp%e hen oy is too $o% enDymes e$ome %ess a$ti7e) I %ess a$ti7e e/er,oni$ rea$tions that re%ease heat are s%o an so %ess heat re%ease) This $oo%s on oy more an re%eases %ess heat 9e
@eaning of constant
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egati3e feedbac, will maintain a reasonably constant set of conditions but will ne3er remain perfectly constant ;ill be some 3ariation around mean
eed to maintain a body temp • •
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emperature emperature regulation in ectotherms ectotherms • • •
%o not use internal energy sources to maintain their body @uscle contractions generate some heat from increased i ncreased respiration ;hen ectotherm is cold it8ll change beha3iour or physiology to increase absorbption of heat from en3ironment
daptation
9ow it helps regulate temp
Ase internal sources of heat to maintain body temp. tem p. @any chemical reactions are exergonic – release energy in form of heat an increase rate of respiration in li3er ot release heat d3antages "onstant body temp regardless of external temp
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"cti3e in cold and night "an inhabit colder parts of the planet %isad3antages$ " lot of energy from food is used to respire "@ore food reBuired "-ess of energy from food put towards growth
omponent of body in3ol3ed #weat glands
-ungs mouth and nose
9airs on s,in
rterioles leading to capillaries in s,in
-i3er cells
#,eletal muscles
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Response if if te temp hi high
Response if if te temp lo low
#ecret more sweat on s,in water in sweat e3aporates using heat from body to supply latent heat of 3aporisation Panting increases e3aporation of water from lungs tongue and other moist surfaces using latent heat as abo3e 9airs lay 'at little insulation. @ore heat lost by con3ection and radiation Gasodilatation allows more blood into capillaries near the s,in. @ore heat can be radiated from s,in which in pale s,inned people may loo, red Rate of metabolism reduced. -ess heat generated from exergonic exergonic reactions o spontaneous contractions
-ess sweat secreted. -ess e3aporation of water
nimal doesn8t pant
9airs stic, up increases insulation reducing loss of heat from s,in Gasoconstriction reduces 'ow of blood through capillaries.
Rate of metabolism increases.. Respiration generates more heat. #pontaneous contractions (shi3ering) generate heat as muscle cells respire more
!eha3ioural mechanisms – mo3e into shade – mo3e into sun light Orientate body to increase7decrease #. exposed Remain inacti3e and spread out limbs to increase #. – or acti3e and ball up
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D) %ecreased loss of heat to the en3ironment
"""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""" """""""""""""""""""""""""" """"""" """"""""""""""""""""""""" ise in $ore temp Thermore,u%atory $entre in hypotha%amus hypotha%amus ete$ts $han,e Ner7ous system an hormona% system $arry si,na%s to s*in %i7er an mus$%es Less heat ,enerate an more heat %ost Temperature a%%s
Role of peripheral temperature receptors •
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n early warning that body temp may change could help hypothalamus respond Buic,er &f extremities start to cool down may e3entually a:ect core body temp Peripheral temp receptors in s,in monitor temperature in extremities. &nfo is fed to the hypothalamus and can initiate beha3ioural mechanisms
#ensory receptors •
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#pecialised cells – energy transducers con3ert one form of energy to another
PAGE #2 sensory re$eptor ta%e
/enerating ner3e impulses • • •
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#ome protein channels allow mo3ement of ions across membrane &ons ,eep di:using until concentration is eBual on both sides eurones (ner3e cells) ha3e specialised channel proteins specic to ? and a ions hey ha3e a gate which controls controls the permeability of the membrane. hannel is usually ,ept closed eurones also contain carrier proteins that acti3ely transport a out of cell ? into cell. alled sodium7potassium ion pumps. @ore sodium ions are transported out than potassium is trasnrpoted in &nside is negati3ely charged charged – polarised membrane er3e impulse is created by altering permeability to sodium ions s sodium ion channels open sodium ions i ons mo3e across membrane down their conc gradient into cell @o3ement of ions creates a change in i n P.% P.% across membrane &nside becomes less negati3e than outside – depolarisation de polarisation
/enerator potentials • •
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Receptor cells respond to changes in en3ironment /ated sodium ions channels open allow #odium to di:use across membrane into cell. small change in potential caused by 0 or 2 sodium ion channels opening is called a generator potential -arger the stimulus the more gated channels open &f enough sodium ions enter the cell potential di:erence changes and will initiate an impulse or action potential
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Once stimulus detected and energy con3erted to depolarisation of receptor cell membrane impulse must be transmitted to other parts of body. body. &mpulse transmitted tr ansmitted across neurone as an action potential %i:erent types of neurones$ #ensory – arry action potential from sensory to # @otor – # to e:ector Relay – onnect sensory and motor
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=unction =unction of neurone is to transmit P from one part of body to another
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#tructure to function of neurone • •
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-ong so can transmit P o3er long dstance Plasma membrane has many gated ion channels that control entry7exit of a7? or ions a7? pumps that use P to acti3ely transport a ions out cell and ? i nto cell @aintain P.% across plasma membrane #urrounded by fatty sheath called myelin sheath (group of #chwann cells) that insulates neurone from electrical acti3ity from nearby cells. here are gaps between between where the #chwann cells meet called nodes nodes of ran3ier 9a3e a cell body that contains nucleus many mitochondria and ribosomes @otor ha3e cell body outside # and ha3e long axon #ensory ha3e long %endron positioned outside #. #ensory ha3e short axon #ensory and @otor ha3e many dendrites connected to other neurones
Resting neurone • •
;hen a neurone is not transmitting H rest lways acti3ely transporting ions across its plasma membrane.
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a7? pumps use P to mum D a out72 ? in. @embrane is more permeable to ? that it is to a and so many ? di:use bac, out ytoplasm has anions and interior of cell is maintained at a negati3e potential Potential di:erence across cell membrane is about "41mG. "41mG. H Resting potential
ction potential • • • •
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t rest a ion channels ,ept closed a7? pump uses P to pump in ? to the axon few ? di:use bac, out and some ? channels are still open &f some a are open a will Buic,ly di:use down conc gradient into cell from surrounding tissue 'uid auses depolarisation of membrane &n generator region of receptor cells the gated channels are opened by changes in en3ironment <.g. pacinian corpuscle which detects pressure changes are opened by deformation he gates further along neurone are are open by changes in P% across across membrane. hey are 3oltage gated channels. /enerator potentials in sensory are depolarisaitons of ccell membrane small depolarisation has no e:ect but if it reaches the threshold potential of "C1mG it8ll open up nearby 3oltage gated channels causing in'ux of a ions and %epolarisation of the membrane will now reach +K1mG causing an action potential Once action potential starts it8ll continue till end of neurone ction potential consist of a set of ionic mo3ements across cell membrane when correct channels are open 0) @embrane @embrane starts starts in resting resting state state polarised polarised " "41mG "41mG compared compared to outside 2) #odium ion ion channels channels open and some some sodium sodium ions di:use di:use into cell cell D) @embrane @embrane depolarises depolarises becomes becomes less negati3 negati3e e and reaches reaches threshold threshold 3alue of "C1mG K) Goltage gated gated a ion ion channels channels open and and a come in. – !ecomes !ecomes positi3ely charged in respect to outside C) Potential di:erence across across plasma plasma membrane reaches reaches +K1mG. +K1mG. &nside &nside of cell is positi3e compared with outside 4) a ion channels channels close close ? channels channels open 6) ? ions di:use di:use out of cell bringing bringing P% bac, to negati3e. negati3e. – Repolari Repolarisatio sation n 5) P% o3ershoot o3ershoots s sli slightly ghtly ma,ing cell hyperpo hyperpolarised larised L) Original Original P% is restored restored so so cell returns returns to to resting resting state state fter P a and ? are in wrong place – restored by a7? pumps Refractory period H time ta,en to reco3er from an action potential lso ma,es sure P are transmitted in 0 direction
-ocal urrents
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Opening of a ion channels at one particular point upsets balance of a and ? ions created by a7? pumps reates a local current in cytoplasm of neurone. hese cause a channels along membrane to open ";hen P occurs a ion channels open at a particular parti cular point "llows a ions to di:use across membrane from outside neurone to inside "@o3ement of a ions into neurone neu rone upsets balance of ionic conc "onc of a ions inside neurone rises where3er the a ion channels are open "auses a ions to di:use sideways away from region of high conc "his mo3ement is called -ocal current
Goltage gated a &on channels • • • •
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=urther along membrane are more gated a &on channels /ates are operated by changes in 3oltage across membrane t rest 3oltage is "41mG inside neurone @o3ement of a ions along the neurone alters the potential di:erence across membrane ;hen P% across membrane reduced gates open llows a ions to enter the neurone at a point further along the membrane ction potential has mo3ed along neurone
he @yelin #heath •
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hey are an insulating layer of fatty material. a7? can8t di:use through this he ionic mo3ements that create create an action potential cannot occur much much o3er the length of the neurone /aps in myelin sheath are gaps between #chwann cells that ma,e up the myelin sheath &onic exchanges cause P to occur only at notes of ran3ier &n myelinated neurone local currents are elongated and a ions di:use along neuroen from one node to another @eans that P >umps " called #altatory conduction
d3antages of #altatory conduction •
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P can only occur at gaps between #chwann cells that ma,e up myelin sheath #peeds up transmission7conduction of P at around 021m "0
#tructure of cholinergic synapse • • •
#ynapse is gap between 2 or more neurones. /ap between two neurones H synaptic cleft – 21nm wide #ynapses that use acetylecholine as neurotransmitter are called cholinergic synapses
#ynatpic ,nob$ • •
@any mitochondria – reBuires a lot of P – acti3e process -arge #
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Gesicles of cetylcholine Goltage gated a ion channels
Post synaptic membrane • •
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ontains a ion channels that respond to transmitter substance hannels made out of C polypeptide molecules. 2 ha3e a special receptor site specic to acetylcoline ;hen acetylcholine binds to the two receptors a ion channels open.
ransmission ransmission across synapse synapse
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0) P arri3 arri3ed ed at synap synaptic tic ,nob ,nob 2) Goltage oltage gated gated a chann channels els open open D) a di:use into into synaptic synaptic ,nob causing causing synaptic synaptic 3esicle 3esicles s to mo3e and fuse with presynaptic membrane K) cetylcholi cetylcholine ne released released by exocytos exocytosis is and di:use across across cleft C) !inds to receptor receptor sites sites on a ion ion channels channels in post post synaptic synaptic membrane membrane 4) a ion channels channels open and a di:uses di:uses across across postsyna postsynaptic ptic membrane membrane into postsynaptic neurone 6) generator potential potential or excitat excitatory ory postsynapt postsynaptic ic potential potential (<#P#) is created 5) &f suFcient suFcient generator generator potentials potentials combine combine then potentia potentiall across postsynaptic membrane reaches the threshold potential L) new P P is created created in in post post synaptic synaptic neurone neurone cetylcholineesterade in synaptic cleft. 9ydrolyses acetylecholine to ethanoic acid and coline #tops trasnmsisions of signals so synapse doesn8t continue to produce P hey are recycled recycled and renter synaptic ,nob by di:usion where they they are recombined to acetylcholine using P ction potentials are all or nothing responses
Other roles of synapses •
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Presynaptic neurones might con3erge to one postsynaptic neurone allowing signals from di:erent parts of the ner3ous ne r3ous system to create the same response. Aseful when se3eral di:erent stimuli One presynaptic neurone might di3erse to se3eral postsynaptic neurones. llow one signal to be transmitted to se3eral places. Aseful in the re'ex arc #ynapses ensures it is in correct direction and one direction #ynapses can lter out low le3el signals -ow le3el signals can be amplied by summation. &f a low le3el signal happens a lot it will generate se3eral successi3e action potentials. Post synaptic generator signals combine to form P. P. #ummation can also occur when se3eral presynatpic neurones each release small numbers of 3esicles into one synapse cclimatisation – #ynapse H fatigued when its run out of transmitter substance. @eans that our ner3ous system no longer responds to stimulus
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for example a smell of perfume or bac,ground noise. 9elps a3oid o3erstimulation of an e:ecter which could damage it reation of specic pathways of conscious thought and memory he pathways created created by synapses enable ner3ous system to con3ey a wide range of messages
=reBuency of transmission •
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;hen a stimulus is at higher intensity more generator potentials produced auses more freBuent P in sensory Our brain can determine intensity of stimulus through freBuency of signals arri3ing
@yelinated and non myelinated neurones • •
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07D of peripheral neurones neu rones are myelinated #heath consists of se3eral layers of membrane and thin cytoplasm from the #chwann ell odes of ran3ier occur at inter3als of 0"Dmm – node is roughly (2"Dum long) Remainder of peripheral neurones are most of the neurones in # are not myelinated. on myelinated at still associated with #chwann cells cel ls but will only ha3e the odd one or so. @eans that action potential tra3els along neurone as a wa3e and doesn8t >ump
d3antage of myelination • •
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@yelinated tra3els at 011"021ms"0 – non myelinated tra3els at 2"21ms "0 arry signals from sensory to # and # to e:ectors o3er long distances -ongest neurone in human is about 0metre
Ases blood circulation to transport signals 9ormones Released from endocrine glands – ductless glands. onsist of group of cells that produce and release the hormone into blood capillaries running through the gland
hese don8t release hormone hormone they ha3e small duct or tube that carries their secretion to another place. <.g. sali3ary gland secrete sali3a i nto a duct and 'ows into mouth
argeting argeting the signal
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ell recei3ing hormone must ha3e a complementary receptor his means hormone can tra3el tra3el around blood without a:ecting a:ecting cells that don8t ha3e a complementary receptor arget arget cell$ cells that possess possess specic receptor on their plasma membrane. #hape is complementary to the hormone molecule. @any cells form together to form a tissue
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2 types of hormone$ "protein and peptide hormone (insulin and glucagon) and deri3ati3es of amino acids (adrenaline) "#teroid hormones (sex hormones) Protein hormones are not soluble in the phospholipid membrane and don8t enter the cell #teroids can pass through membrane and enter the cell to ha3e direct e:ect on %
drenaline – amino acid deri3ati3e – unable to enter target cells @ust cause e:ect inside the cell without entering it – the binds onto receptor of cell surface membrane Receptor is associated with an en*yme on inner surface of cell membrane called denyl yclase drenaline binds to receptor. receptor. drenaline is called the rst messenger ;hen it binds it acti3ates en*yme adenyl cyclise which w hich con3erts P P to cyclic @P (c@P). amp is the second messenger and causes an e:ect inside cell by acti3ating en*yme action
=unctions =unctions of adrenal gland •
-ying abo3e ,idneys one on each side of the bond. an be di3ided into medulla region and cortex region @edulla$ "=ound in centre of gland. Release adrenaline when pain7shoc,. @ost cells ha3e adrenaline receptors. <:ect is to prepare body for acti3ity$ acti3ity$ "Relax smooth muscle in bronchioles "&ncrease stro,e 3olume of heart. &ncrease heart rate. Gasoconstriction Gasoconstriction to raise blood pressure. #timulate con3ersion of glycogen to glucose. %ilate pupils. @ental awareness. &nhibit action of gut. !ody hair erect drenal cortex$ "Ases cholesterol to produce certain steroid hormones "@ineralcorticoids (ladosterone) to help control conc of ?7a in blood "/lucocorticoids (cortisol) help to control metabolism of carbohydrates8 and protein in li3er
Regulation of blood glucose
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Pancreas Pancreas is a small organic under stomach – has exo and endocrine system Releases digesti3e en*ymes – exocrine part ells found in small groups surrounding tubules into which they secret digesti3e en*ymes – the tubules >oin up to form pancreatic duct. Pancreatic Pancreatic duct carries 'uid containing en*yme into rst part of small intestine =luid$ mylase (carbohydrase) rypsinogen rypsinogen (&nacti3e protease) -ipase =luid contains sodium hydrogen carbonate ions ma,ing itt al,aline helping neutralise contents of digesti3e system that ha3e left stomach acid Pancreas Pancreas has &slet of -angerhans containing di:erent types of cells. 2 types – lpha cells – #ecrete hormone glucagon !eta cells – @anufacture and secret &nsulin &slets are well supplied with blood capillaries capill aries and these hormones go into capillaries –
!lood glucose is carefully regulated &slets of langerhans monitor conc of glucose in blood. ormal blood conc is L1mg 011cm"D. OR K and 4mmol dm"D &f conc rises or falls fall s alpha and beta cells detect change and respond by releasing hormone
&f blood conc. too high •
oo oo high beta cells secrete insulin into blood bl ood target cells hepatocytes muscle cells and other body cells including those in brain possess specic membrane bound receptors for insulin !lood passes these cells and the insulin binds to receptors 2nd messenger system acti3ates a series of en*yme controlled reactions in cell <:ects of insulin on li3er cells$ "@ore glucose enters cell through glucose channels "/lucose in cell is con3erted to glycogen for storage (glycogenesis) "/lucose con3erted to fats "/lucose used in respiration &ncrease in entry of glucose through channels reduces blood glucose conc
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I %oo ,%u$ose $on$ too %o 9ete$te y A%pha $e%%s an they se$rete hormone ,%u$a,on Tar,et $e%%s are the hepato$ytes E=e$ts are #"$on7ersion o ,%y$o,en to ,%u$ose (,%y$o,eno%ysis" 2" use o atty a$is in respiration
" Prou$tion o ,%u$ose y $on7ersion rom amino a$is an ats (,%u$oneo,enesis" O7era%% e=e$t is to in$rease %oo ,%u$ose $on$
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&nsulin secreted when blood glucose is high – when its low secretion needs to stop ontrol of insulin secretion 0) ell membrane membrane of of ! cells cells contain contain a and ? ion channels channels 2) ? ion channels channels are are normally normally open and normal normal closed. closed. ? di:uses di:uses out of cell ma,ing inside more negati3e. P% of membrane H "61mG D) ;hen glucose glucose conc outside outside is high high glucose glucose molecules molecules di:use di:use into cell K) /lucose /lucose is Buic,ly Buic,ly used in metabol metabolism ism to produce produce P P C)
%iabetes @ellitus • • •
!ody can no longer control its blood glucose conc an lead to 3ery high conc. of glucose – 9yperglycaemia 9ypoglycaemia – blood glucose conc too low
ype ype 0 diabetes • •
&nsulin dependent – starts in child hood Result of autoimmune reponse in which bodys own immune system attac,s beta cellas and destroys them. Results from a 3iral attac, – body is no longer able to manufacture suFcient insulin and cannot tore excess glucose and glycogen
ype ype 2 diabetes • • •
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on insulin dependent 9appens in older age – responsi3eness to insulin declines #pecic receptors on the surface of the li3er and muscle cells decline and cells lose ability to respond to insulin in blood -e3els on insulin secreted by !eta cells may decline. =actors contributing to this$ obesity high sugar diet sian or fro aribbean family history.
reatment reatment •
ype ype 2 – @inotiring and control control of diet. @atch carbohydrate inta,e inta,e and use. <3entually be supplemented by insulin in>ections or use of other drugs which slow down the absorption of o: glucose from digesti3e system
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ype ype 0 – insulin in>ections. !lood glucose conc must be monitored monitored and correct dose of insulin must be administered to ensure glucose conc remains fair stable
d3antages of genetically engineered bacteria to produce insulin instead of using ones from animals • • • • • • •
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ection -ower ris, of infection heaper to manufacture than of animals daptable to demand o moral ob>ections as its not from animals
!lood supplies oxygen nutrients glucose fatty acids amino acids to cells Remo3es waste products such as o2 and urea so they don8t inhibit cell metabolism he heart adapts to body to supply more oxygen oxygen and glucose by$ by$ increasing7decreasing heart rate...&ncrease strength of contractions....Golume contractions....Golume of blood pumped per beat (stro,e 3olume)
Rate at which heart beat is a:ected by many factors • •
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9eart H myogenic – initiate its own contractions Own pacema,er – sinoatrial node. an initiate its own action potential by sending a wa3e of exication o3er atria walls through G G down pur,yne bres to 3entricles causing contractions 9eart is supplied by ner3es from medulla oblongata of brain. hese connect to # and do not initiate a contraction but can a:ect freBuency of contractions. P sent down accelerator ner3e increase the heart rate. P sent down 3agus ner3e reduce heart rate
Ander resting conditions heart rate is controlled by # # 41"51 per minute usually – freBuency controlled by cardio3ascular centre in medulla oblongata. =actors a:ecting heart he art rate$ 0) @o3ement @o3ement of limbs detected detected by stretch stretch receptors receptors in muscles muscles send send impulses to cardio3asulcar centre informing that extra oxygen may be needed usually increasing heart rate 2) ;hen we exercis exercise e O2 produced. produced. #ome #ome reacts reacts with water in blood blood plasma reducing P9 which is detected by chemoreceptors in carotid arteries aorta and the brain. hemoreceptors send impulses to cardio3asulcafr centre which increases heart rate D) ;hen we stop exerci exercising sing O2 O2 conc falls reducin reducing g acti3ity acti3ity of accelerator pathway reducing heart rate K) drenaline drenaline secreted secreted in response response to stress stress shoc, shoc, anticipation anticipation or excitement. Presence Presence of adrenaline increases heart rate helping prepare the body for acti3ity
C) !lood pressur pressure e monitored monitored by stretch stretch receptors receptors in walls of carotid sinus sinus which is a small swelling in carotid artery. artery. &f blood pressure is too high stretch receptors send signals to cardio3ascular centre which responses by reducing heart rate %&/R@ P/< 2L
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rticial rticial pacema,ers pacema,ers deli3er impulses impulses 3ia electrode electrode pad on s,in. #imilar #imilar method to electrical chair was 3ery painful 0LC1 – patient wear small plastic box with wires inserted through s,in to act as electrons on heart muscle @odern pacema,ers only Kcm long and implanted under s,in and fat on chest and are responding on acti3ity of patient #ome deli3er impulses to 3entricle walls. his deals with conditions where G normally relays the impulse from atria to 3entricles 3ia pur,yne bres is not functioning but the # maybe.
Respiration is where energy stored in complex organic molecules(carbs fats proteins) is used to ma,e P E/ists as potentia% ener,y an *ineti$ ener,y 1o%e$u%es ha7e *ineti$ ener,y that a%%os them to i=use on a $on$entration $on$entration ,raient
@etabolic process$
A$ti7e transport & mo7in, ions an mo%e$u%es a$ross a memrane a,ainst $on$entration ,raient) -oium'Potassium pumps use this -e$retion & %ar,e mo%e$u%es mae in $e%%s e/porte y e/o$ytosis Eno$ytosis & u%* mo7ement o %ar,e mo%e$u%es into $e%%s -ynthesis o %ar,e mo%e$u%es rom sma%%er ones su$h as proteins rom amino a$is sterois rom $ho%estero% an $e%%u%ose rom ; ,%u$ose) & E/amp%e o anao%ism 9NA rep%i$ation an synthesis o or,ane%%es 1o7ements & a$teria% 5a,e%%a eur*aryoti$ $i%ia an unu%ipia mus$%e $ontra$tion an mi$rotuu%e motors mo7in, or,ane%%es) A$ti7ation $hemi$a%s & ,%u$ose is phophor%ate at e,innin, o respiration so its unsta%e an $an e ro*en on to re%ease ener,y -ome ener,y rom $atao%i$ rea$tions is re%ease in heat orm) ;here does energy come fromE •
Plants Protoctists Protoctists and bacteria " " " Photoautotrophs
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Respiration releases energy to phosphorylate %P to ma,e P P
Role of P • • •
P is a nucleotide – denosine (adenine and ribose) + D phosphate an be hydrolysed to %P and Pi releasing D1.4,> energy per mol. %escribed as uni3ersal energy currency
P + 921
%P + 921
@P + 92O
%<O#&<
he 92O added is the substance substance being hydrolysed hydrolysed 0st step produces D1.4,M mol 2 nd step D1.4,M mol D rdstep 0K.2,M mol Pi is produce at each step. &t8s a condensation reaction the other way. way. P #ynthase is used here K stages of respiration •
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/lycolysis – 9appens in cytoplasm. %oesn8t need oxygen can be aerobic or anaerobic. /lucose is bro,en down to 2 molecules of pyru3ate -in, reaction – happens in mitochondrial matrix Pyru3ate is dehydrogenated and decarboxlyated and con3erted to acetate ?rebs cycle – 9appens in mitochondrial matrix – acetate is decarboxylated and dehydrogenated Oxidati3e phosphorylation – a,es a,es place on folded inner membrane (crisate) of mitochondria %P is phophorylated to P ?rebs -in, and Oxidati3e ta,e place under aerobic conditions &f it8s anaerobic pyru3ate is con3erted to either
oen*ymes •
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&n lin, glycolysis and ,rebs 9 atoms are remo3ed from substrate molecules in oxidation reactions – catalysed c atalysed by dehydrogenase
% •
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on organic non protein molecule helping the dehydrogenase en*yme carry out oxidation reactions @ade out of 2 nucleotides from nicotinamide ribose adenine and 2 phopsphate. he nicotinamide acceots hydrogens hydrogens ;hen % has accepted 2 hydrogens it becomes %9 % used in glycolysis lin, ,rebs and anaerbobic ethanol and lactate pathways
oen*yme
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denosine D phosphate pantothenic (3itamin !C) acid and a small cystemaine group (amine and sulphur)
G%y$o%ysis 9appens in cytoplasm – K stages$ Phosphorylation "/lucose is stable and needs to be acti3ated before it can be split into two "One P molecule is hydrolysed and phosphate group released attaches to the glucose at carbon 4 forming /lucose 4"phosphate "/lucose 4"phosphate turned into fructose 4"phosphate "nother P is hydrolysed and phosphate attaches to the fructose at carbon 0. "=ructose "=ructose 04 biphosphate is i s now formed "he energy from hydrolysed P acti3ates hexose sugar and pre3ents it from from bein being g tran transp sport orted ed out out of the the cell. cell. &t8s &t8s now now call called ed 9ex 9exose ose 04 04 biphosphate "2 P molecules ha3e been used for O< glucose molecule #plitting of hexose 04 biophsphate " #pli #plitt int into o two two mol molec ecul ules es of tri trios ose e phos phosph phat ate e
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Oxidation of triose phosphate "naerobic process in3ol3ing oxidation "2 hydrogens are remo3ed from each triose phosphate "&n3ol3es dehydrogenase en*ymes "ided by % which accepts the hydrogen atoms forming %9 "#o far 2 molecules of % are reduces for each molecule of glucose " 2 molecules of P are formed called substralte le3el phosphorylation
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on3ersion of triose phosphate to pyru3ate "K en*yme catalysed reactions con3ert triose phosphate to pyru3ate (D carbon compound) "2 molecules of %P are phospohorylated to two molecules of P by substrate le3el phospohorlyation Products of glycolysis (per each glucose molecule) 2 mo%e$u%es o ATP ( 2 use 3 ,aine net 8 2" 2 mo%e$u%es o NA9H & $arry hyro,en to the inner mit$honria% memrane an e use to ,enerate more ATP urin, OP 2 mo%e$u%es o pry7uate & a$ti7e%y tansporte to mito$honria% matri/ or ne/t sta,e o aeroi$ respiration) @itochondria • •
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9a3e an inner and outer phospholipid membrane ma,ing up an en3elope Outer membrane is smooth and inner folded into cristae (gi3es a larger surface area) he matrix is enclosed by the inner membrane
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@atrix is semi"rigid gel li,e consisting of lipids and proteins. lso has mitochondrial % Ribosomes and en*ymes Rod or thread li,e. @ost are 1.C"1.0um in diameter and 2"Cum. thletes ha3e larger mitochondria @etabolically acti3e cells ha3e larger demand for P and so more mitochondria hese usually are longer longer and ha3e more densely pac,ed pac,ed cristae for more electron transport chains and more P P synthase en*ymes. an be mo3ed around by cytos,eleton. #ynaptic ,nobs ha3e lots of mitochondria around them permanently as it has a high P demand.
#tructure to function (matrix)
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1atri/ is here %in* rea$tion an Fres $y$%e @olecules of % Oxaloacetate – K carbon compound – accepts acetate from lin, @itochondrial % codes for mitochondrial en*ymes and other proteins @itochondrial ribosomes where proteins are assembled
#tructure to function (outer membrane) •
ontains proteins to form channels to allow pyru3ate to pass. 9as en*ymes too
#tructure to function (&nner membrane) •
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%i:erent lipid composition and is impermeable to small ions and hydrogen ions =olded to cristae to increase surface area
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P #ynthase en*ymes • •
-arge and protrude from inner membrane into the matrix ?nown as stal,ed particles
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llow protons to pass through them
Protons 'ow down proton gradient through P synthase into matrix from inter membrane – hemiosmosis =orce =orce dri3es the rotation of part of the en*yme and allows %P and Pi to be >oined forming P P.. oen*yme =% =% becomes reduced in ?rebs cycle is bound to a dehydrogenase en*yme which is embedded in the intermembrane. i ntermembrane. he hydrogen atoms accepted by =% don8t get pumped into i nto the inertmembrane space. hey pass bac, into the matrix instead
=% H Ribo'a3in adenine ribose and two phosphate
-in, reaction and ,rebs cycle •
Pyru3ate produced in glycolysis is transported across inner and outer mitochondrial membranes into the matrix
-in, reaction " " "( 2pyru3ate + 2o •
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2o2 + 2%9 + 2o
%ecarboxylation and dehydrogenation of pyru3ate to acetate are catalysed Pyru3ate dehydrogenase remo3es 9 atoms Pyru3ate hydrogenase also remo3es carboxyl group which becomes o2 % accepts 9 atoms oen*yme accepts acetate forming cetyl oen*yme . o carries acetate to ,rebs o P P is produced but the %9 will ta,e a pair of 9 atoms to inner mitochondrial membrane and will be used to ma,e P in oxidati3e phosphorylation
?rebs ycle • •
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a,es a,es place in mitochondrial mitochondrial matrix cetate from cetyl oen*yme >oins with Oxaloacetate forming citric acid. oen*yme is released and goes bac, to collect more acetate itrate is decarobxylated and dehydrogenated to form a C carbon compound. Pair of hydrogen atoms is accepted by % which becomes reduced C carbon compound is decarboxlyated and dehydrogenated to form K carbon compound and another %9 K carbon is changed to another K carbon and %P is phosphorylated to produce a molecule of P – #ubstrate le3el phosphorylation he second K carbon compound is changed to another K carbon compound. Pair of hydrogen atoms is remo3ed and accepted by =% forming =%9. he K carbon compound is dehydrogenated dehydrogenated and regenerates oxaloacetate. oxaloacetate. nother % is con3erted to %9
Product per glucose %9 =%9 o2 P
-in, reaction 2 1 2 1
?rebs cycle 4 2 K 2
Oxygen isn8t used but these stages won8t occur without oxygen so are aerobic Other food substrates that are glucose can be respired =atty acids bro,en down to acetate can enter ?rebs mino acid can be demainated de mainated (92 remo3ed) and the rest of the molecule can enter ?rebs or can be changed to Pyru3ate or cetate.
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=inal stage of aerobic respiration • •
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&n3ol3es < embedded in inner mitochondrial membranes %9 and =%9 are reoxidised reoxidised when they donate 9ydrogen atoms which are split into protons and electrons to the electron carriers he rst < to accept electrons electrons from %9 is called %9 %9 %ehydrogenase ( %9"oen*yme N reductase) Protons go into the solution in the matrix
< < •
hemiosmosis •
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s electrons 'ow along the < energy is released and used by coen*ymes associated with the < to pump protons across the inter membrane space !uilds up a proton7ph gradient and a electrochemical gradient Potential energy therefore builds up in the intermembrane space 9 ions cannot di:use through lipid part of the inner membrane bbut can di:use through ion channels in it. hese channels are associated with P synthase.
O/iati7e phosphory%ation phosphory%ation •
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=ormation of P P by addition of inorganic i norganic phosphate to %P in presence of oxygen. Protons 'ow thorugh P synthase dri3e rotation of en*yme and >oin %P and Pi H P oin so oxygen is reduced to water. "Kh+ + Ke" + o2 292O
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=or each glucose molecule 2 P ha3e been gained in glycolysis 2 P ha3e been made in ?rebs. @ore P P will be made in oxidati3e phosphorylation where %9 and =%9 are reoxidised
ame of molecule %9 =%9
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/lycolysis 2 1
-in, 2 1
?rebs 4 D
%9 and =%9 pro3ide electrons to < used in oxidati3e phosphorylation %9 pro3ides 9 ions that contribute to the build up of proton gradient for chemiosmosis. =%9 =%9 stay in matrix m atrix but combine with oxygen to form water 01 molecules of @%M can produce 24 molecules of P during oxidati3e...... otal otal yield of P P molecules per glucose H D1 his is rarely achie3ed because$ "#ome protons lea, across mitochondrial membrane reducing proton to generate proton moti3e force "P "P used to acti3ely transport pyru3ate into mitochondria "P "P is used to bring hydrogen from %9 made during glycolysis into mitochondria
P/< L2 "LD •
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&f oxygen is absent < < can8t function and so ?rebs and lin, will sotp. Only way to produce P is then glycolyisis. Reduced % generated from oxidation of glucose has to be reoxidised for glycolysis to ,eep occurring
=or eu,aryotic cells there are to pathways to reoxidise % • •
=ungi yeast use ethanol fermentation nimals use lactate fermentation
-actate =ermentation • • •
@ammalian tissue during 3igorous acti3ity when demand for P is high %9 has to be oxidised to % Pyru3ate is hydrogen acceptor accepting from %9
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% is now oxidised and is a3ailable to accept more hydrogen atoms from glucose /lycolysis can continue generating ;P
lcohol fermentation • •
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Pyru3ate loses O2 molecule – %ecarboxylated to ethanal atalysed by pyru3ate decarboxylase and has a coen*yme (thiamine dipohsophate) bound to it
@ore protons H @ore P @ore 9ydrogen atoms in a molecule of respiratory substrate the more P P can be generated when it is respired. @ore hydrogen H more oxygen needed to respire nimals store glucose as glycogen plants as starch =ructore7/alactose are changed to glucose for respiration heoretical yield for glucose is 2561 ,M mol"0 a,es a,es D1.4,M to produce produce 0 mol P P heoretically respiration of 0 mol of glucose should produce produce nearly LKmol of P ctual yield is D1mol D1m ol P D2 eFciency Remaining energy released as heat which helps maintain a suitable body temp
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riglycerides riglycerides are hydrolysed hydrolysed by lipase to fatty acids acids and glycerol /lycerol can be con3erted to glucose then respired fatty acids cnat =atty acids ha3e many proteins for oxidati3e phosphorylation so they produce a lot of P
Respiratory substrate arbohydrate -ipid Protein
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@ean energy 3alue ,> g"0 0C.5 DL.K 06
Role of loop of 9enle is to create a low water potential in the tissue of the medulla
-oop of 9enle • •
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onsists of descending limb descending into the medulla (scending limb into the cortex)
rrangement allows salts (l and ions) to be transferred from ascending to descending O3erall e:ect is to increase conc. of salt in the tubule 'uid and conseBuently they di:use out of thin walled ascending limb into the surrounding medulla tissue gi3ing gi3ing tissue 'uid in medulla 3ery low water potential s 'uid descends deeper into medulla – water potential becomes lower because$ "-oss of water by osmosis to surrounding tissue 'uid "%i:usion if a and l ions into tubule from surrounding tissue 'uid s 'uid ascends bac, water potential becomes become s higher because$ "!ase of tubule a and l di:use out of tubule into tissue 'uid "9igher up tubule a and , are acti3ely transported out into the tissue 'uid rrangement of loop of 9enle is ,nown as a hairpin counter current multiplier <:ect of this arrangement is to increase eFciency of salt transfer from ascending limb ot descending limb. auses a build up of salt conc. in surrounding tissue 'uid
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@o3ement of salts from ascending limb into medulla creates high salt conc in tissue 'uid so low water potential Remo3al of ions from ascending limb means at the tp of ascending limb the urine is dilute ;ater may then be reabsorbed from urine in teh distal tubule and collecting duct mount of water reabsorbed depends on needs of body ?idney is also an organ of osmoregulation ollecting duct op op of ascending limb the tubule 'uid 'uid passes along a short distal distal con3ulatoed tubule where acti3e transport is used to ad>ust the cconc of 3arious slats hen goes to collecting duct and atm tubule 'uid contains a lot of water – high water potent ollecting duct carries 'uid bac, down medulla me dulla into pel3is issue 'uid in medulla has a low water ptent that becomes becomes e3en lower deeper int the medulla s tubule 'uid passes down collecting duct water mo3es by osmisos from tissue to surrounding 'uid hen tners the blood capillaries by osmosis osmosis and is carried away mount of water reabsorbed depnds on permeability of walls in collecting duct !y time urine reaches pel3is it has lower wwater potential and conc of urea and salts in urine is higher htran that of blood plasma
Osmoregulation • • • • • •
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ontrol of water le3els and salt le3els in the body ;ater gained from f rom food drin, metabolism (respiration)( ;ater lost from urine sweat water 3apour in exhaled air faeces ool day – a lot of drin, – large 3olume conc urine 9ot day – little drin, – small concentrated urine ;alls of collecting duct can be made more7less permeable depending on needs 9ot day more permeable walls so more water is ,ept in ;alls respond to %9 le3el – ells el ls in walls ha3e %9 receptors %9 binds causing en*yme controlled reactions auses 3esicles containing water permeable channels (aBuaporins) into the cell surface membrane. @a,es the walls more permeable to water. @ore %9 H @ore Buaporins &f less %9 cell surface membrane folds inwards to create new 3esciles that remo3e water permeable cahnnels from the membrane. @a,es the wals less permeable and less water is reabsorbed by osmosis.
;ater potential is monitored by osmoreceptors in the hypothalamus of the brain
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ells probably respnd to the e:ects of osmosis when the water potential of the blood is low the osmoreceptor cells lose water by osmosis. his causes them to shrin, and stimulate neurosecretory cells in hypothalamus. he neuersecretory cells are are neurones producing producing %9. %9 is manufacted manufacted in teh cell body which lies in the hypothalamus %9 'ows down aaxon to terminal bulb in posterior pituiraty gland and stored till needed ;hen the neuerosecretory cells are stimulated they send action potentials down their axosn and cause release of %9 %9 enters blood capillaries running through posterior pituitary gland and it is transported around body and acts on cells cel ls of the collecting ducts Once water potent of blood rises again %9 released %9 bro,en down – half li,e 21mins. herefore collecting ducts will recei3e less stimulation Page KL diagram
?idney failure • • • •
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an occur by diabetes mellitus 9ypertension &nfection @eans youre unable to remo3e excess water and certain waste products from blood e.g. urea and salt an8t regulate water and salt le3els either ei ther
%ialysis – treatment •
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Remo3es wastes excess excess 'uid and salt from blood by passing o3er a dialysis partially permeable membrane allowing exchange of substances between 'uid and blood %ialysis 'uid contains correct conc of salt urea water and other substances in blood plasma
9aemodialysis •
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!lood is passed into machine that contains an articial dialysis membrane. 9eparin is added to a3oid clotting and any bubbles are remo3ed before blood returns to body. Asually performed at a clinic D times a wee, for se3eral hours
Peritoneal dialysis • • •
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=ilter is the bodys own abdominal membrane permanent tube is implanted in abdomen %iaylsysis solution is pour thorugh tube and lls space between abdominal walls and organs fter se3eral hours the used solution is drained out
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Performed in conse3uti3e sessions daily at home or wor,
?idney transplant •
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Patient is under anaesthesia new organ is planted into lower abdomen and attatches it to blood supply and bladder. bladder. Patients feel much better after transplant &mmune system will recognise new organ as foreign and produce a reaction so immunosuppressant drugs are gi3en to pre3ent re>ection
d3antages$ • • • • •
"=reedom "=reedom from time consuming dialysis %iet is less limited =eel better !etter Buality of life o longer seeing as chronically ill
%isad3antages • • • • •
&mmunosuppressant drugs are needed for lifetime of ,idney , idney @a>or surgery Ris, of surgery – infection bleeding damage to surrounding orangs =reBuent chec,s of organ re>ection nti re>ection medicines cause 'uid retention and high blood pressure more susceptibility to infections.
Pregnancy test$ • • • •
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9/ is small glycoprotein with molecular mass of D4611. =ound in urine 4 days after pregnant. @onoclonal antibodies. ntibody only binds with 9/. nti body has blue bead. @obilised anti bodies at the bottom. 9/ anti body complex mo3es up to the strip until it stic,s to a band of immobilised antibodies op op line is a test with mobile and immobilised antibody complex
esting esting for anabolic steroids • • •
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&ncrease protein synthesis within cells @ore cell tissue in muscles and gi3e ad3antage in sports 9alf life of 04 hours and remain in blood for days – time ta,en for substance for its conc to drop to half #mall molecules and can enter nephron easily esting esting it reBuires gas chromatography7mass spectrometry7 spectrometry7 urine sample /as is 3aporised in presence of gaseous sol3ent and passed down a long tube lined by an absorption agent.
