A2 Excretion

HideShow resource information


What is excretion? The removal from where? What is metabolic waste? Where does it come from?

What are cell products formed from? When do they need to be removed? What are the two very large waste products? Whats CO2 a product of? give an example of nitrogen containg compounds? What produces co2? Where is urea produced? From excess what?

Where is co2 passed from the cells to? What is it transported in? mostly in what form? To where? What does it do in the lungs? How is it excreted? How is urea produced? Where? What is this process called? where is the urea passed? To be transported where? What is is transported in? whats meant by solution? What happens to it in the kidnes? To becomea  part of what? Where is urine stored? What is that excreted via?

1 of 30


the removal of metabolic waste from the body, from the bod, waste substances that may be toxic or are produced in excess by reactions in the cells, by-products of unwated subsatnces from normal cell process,

chemical process occuring in the cells, when they are toxic or in excess, carbon dixoide and nitrogen containing compounds, respiration, urea, every living cell in the body as a result of respirtation, liver from excess amino acids,

bloodstream, blood, hydrogencarbonate ions, lungs, difuses into the alvoli to be excreted as we breathe out, breaking down excess amino acids in the liver, deamination, into the bloodstream, kidneys, solution, dissovled in the plasma, removed from the blood to becom a part of urine, bladder before being excretd via the urethra

2 of 30


What is wrong with excess co2? Where is the majority of co2 carried? In what form? What does forming hydrogencaronate ions also form? Where does this opccur? Under the influence of what enzyme? What do the hydrogen ions combine with? What do they compete with? For what? What If there Is to much co2 in the blood then? How does co2 also combine with haemoglobin? To form what? What is the affinity of this molecule? What can excess co2 also cause? where does the co2 dissolve? Once dissolved what can it combione with? To produce what? Give the formula? What does the carbonic acid do? realsing? Give the formaula? What do the hydrogen ions do? making the blood more? What do proteins in the blood act as? To do what? What if the change in PH is small? Where? What does this cause an increase? To do what? If the blood ph drops below 7,35 what can it result in? what may there also be a rapid change in? what is this known as? What can it be caused by also? Such as? What can also induce respiratory acidosis? “Review co2 production AS spread 1.2.12.”

What cant the body store? What makes it wasteful to just excrete them though? What happes instead? what happens their? Whats this called? what does the amino group inititlaly form? What is it coverted to? Called? which is transpotrted where? For what? What can the remaining keto acid be used for? Or be converted to? Give the formula for deamination? Ad the formaqtion of urea?

3 of 30


toxic, the blood, hydeogencarbonate ions, hydrogen ions, red blood cells, influence of the enzyme carbonic anhydrase, combine with haemoglobin, compete with oxygen for space on the haemoglobin, reduce oxygen transport, combines directly with haemoglobin to orm carbaminohaemoglbin, lower afinity for oxygen than normal haemoglobin, respiratory acidosis, dissolves in the blodo plasma, water to rpdice carbonic acid, co2+h20=h2co3, dissociates to realse hydeogen ions, h2c03=H++HCO3-, lower teh ph, acidic, buffers to resist the change, the extra hydrogen ions are detced by the respiratory centre in the medulla oblongata of the brain, increase in breathing rate to remove the excess co2, slowed or difficult breathing headache drowsiness restlenss tremor or confusion, rapid heart rate and change in blood pressure, respiratory acidosis, diseases or conditions that affect the lungs themselves, emphysema chronic brontitis asthma severe pnuemnia, blockage of the airway due to sweelling a oreign object or vomit

proteins or amino acids, almost as  much energy as carbohydrates, it would be wasteful to excrete excess amino acids, transported to the lvier, the potentially toxic amino group is removed, deamniation, forms the very soluable and highly toxic compound ammonia, to a less soluable less toxic compound called urea, transported to the kidneys for excretion, keto acid can be used diecctly in resportaion to release energy or it may be converted to a carbohydrate or at for storage, Deamination: amino acid +oxygen = keto acid +ammonia, Formation of urea: ammonia _co2=urea+ water

4 of 30

The Liver

What are the liver cells called? what processes do they carry out? What does the liver have an important role in? what is it therefore essential it has? What is the internal structure of the liver arranged to ensure?

How many sources of the blood is the liver usually supplied with? Name one? Where does blood travel from? Via what? Into where? What does this supply for ewhat? Are the liver cells active a lot? Why? What do many of the processes require? In what form? So whats essential? Where does it also get blood? What sort of blood? What does this enter the liver by? Why is the hpatic portal vein unusual? What is this blood rich in? what will be uncontrolled? What may the blood contain? How does blood leave the liver? Where does this rejoib? What does the blood do now? What is the fourth vessel connected to the liver? Is it a blood vessel? What Is bile? What two functions does it have? Whats bile carried in? from where to where? What does it do their?

How are the cells blood vessels and chambers inside the liver arranged to ensure? What is the liver divied into? Which are further divided into? As the hepactic artery and hepatic portal vein enter the liver what do they do? where do these vesels run? What are they kinown as? What do the hepactic aretery and hepatic portal vein do at intervals? What happens to the blood from the two vesssels? Where does it pass? Called? what is the sinusoid lined by? Where does the sinusoid empty? A branch of what? What do the branches of the hepactic vein come from? Whats its function? Whats the sinusoid very close to? So therefore whats close to them? What are the cells able to do? what is one of the many fucntions of the liver cells? What is this released into? What does canaliculi mean? What do they join together to form? Whats that’s function?

5 of 30

The Liver

Hepatocytes, many hundreds of metabolic process, homeostasis, good supply of blood, to ensure that as much blood as possible flows past as many liver cells as possible

2, oxygenated blood from the heart, from the aorta via the hepati artery, into the liver, the oxygen essential for aerobic respiration, very active, many metabolic process, require energy in the form of ATP, good supply of oxygen, deoxygenated blood from the digestive system, enters the liver via the hepatic portal vein, rich in the products of digestion, concentrations of compounds are uncrtolled, may contain toxic compounds that have been absorbed in the intestine, hepactic vein, rejoins the vena cava and the blood returns to normal circulation, bile duct, not a blood vessel, secretion from the liver, digsetive function and excretaroy function, bile from the liver to the gall bladder, stored until required to aid digestion of fats in the small intestine,

the best possible contact between the blood and the liver cells, lobes, divided into cylindrical lobules, split into smaller and smaller vessels, run between and parallel to the lobules, inter-lobular vessels, branches from the hepatic artery and portal vein enter the lobules, the blood from the two vessels is mixed and passes into a chamber called sinusoid, lined by liver cells, empty into the intra-lobular vessel, branch of the heppactic vein, branches from the hepactic vein from differnt lobules join to form the hepactic vien, drains blood from the liver, close contact with the liver cells, remove molecules from the blood and pass molecules into the blood, manufacture bile, into the bile caaliculi (small canal), to form the bile ducts which transports bile to the gall bladder,

6 of 30

The Liver

What are hepatocytyes? Are they specialised or unspecialised? Whats their shape? What do they have many of? where? What do their many metabolic functions include (name 4) what does this mean their cytoplasm has to be? How is it speciailised?

What are kupffer cells? Where are they found? What are they involved in? whats bilirubin? where does it come from? What is it in faeces?

7 of 30

The Liver

liver cells, unspecialised, simple cubodial shape with many microvilli on their surface, include protein synthesis, transformation and storage of carbohydrates, synthesis of cholesterol and bile salts, detoxification andmany other process, ctyoplasm is dense and is speiclised in the amounts of vertain organells that it contains (golgi, vesicles, ribosismes, mitochondria,)

speiclaised macrophages, move about within the sinusoids and are involed in the breakdown and recycling of old red blood cells, bilirubiin which is excretewd as part of the bile and in faeces, brown pigment

8 of 30

Functions of the Liver

What sort of activity does the liver have? It has many functions what three levels does it control? What does it synthesis? Where? What five things does it store? Detoxification of what two things? Breakdown of what? Destruction of what?

How much protein do we need each day? How much is consumed In developed countries? What cant be stored? Why? What do the amino acid molecules contain a lot of? so why don’t we excrete the whole molecule? Where does it undergo treatment then? Before what is excreted? What two processes does it consist of? Give formula?

What does the process of deamination produce? Is it soluable and insoluable? Whats wrong with it? What mustn’t happen? What does it also produce? Called? what can this do? to release? Whats the ornithine cycle? why must ammonia be converted? What is it combined with? To produce what? What cycle does this happen in? why is urea better? Where can it be passed? And transported where? What do the kidneys do? where is urine stored? Until? Give the formula for ornithine cycle?

9 of 30

Functions of the Liver

metabolically, blood glucose amino acid levels and lipid levels, red blood cells in the fetus plasma proteins and cholesterol, vitamins A D B B12 Iron and glycogen, alchol and drugs, hormones, red blood cells,

40-60 g of proteins, developed countries eat more, excess amino acids cant be stored, amine group makes them toxic, amino acids contain a lot of energy so it would be wasteful to excrete the whole molecule, treatmen tin the liver before the amino component is excreted, two process deamination and the ornithine cycle, amino acid --> ammonia -->urea

ammonia, very soluable and highly toxic, must not be allowed to accumulate, orangic compound a keto acid, enter respiration directly to release energy, the process in which ammonia is converted to urea and occurs partyl in the cytosol and partly in the mitochondria as ATP is used, its highly soulable and toxic, less toxic form very quickly, combined with co2 to produce urea, ornithine cycle, less solubale and less toxic than ammonia, into the blood and trasnproted around the body to the kidneys, urea is filtered out of the blood and concentrted in the urine, stored in the bladder, released from the body, 2NH3 +co2-->CO(NH2) + H20

10 of 30

Functions of the liver

What is the liver able to do? give an example of one made in the body? Give an example of one consumed as part of a diet? Give another way a compound could get into our body? What four ways can a toxin be rendered harmless? What do liver cells contain many? That do what? Give one? What does it convert? To what? What does catalase have a high of? meaning? How many? What is detoxification?

What is alchol called? what does it do to nerves? What does it contain? What can that be used for? What cells break it down in the liver? By the action of what enzyme? Whats is the resulting compound? What happens to it further? By what enzyme? What is the final compound produced? What is it combined with? To form what? What process does it enter? What is released? What are they combined with? To form what? Draw the steps? What is NAD required to do? for what? What if there is to much alchol? What happens to these fatty acids? And stored where? Causing the liver to do what? What is this condition known as? What can it lead to?

11 of 30

Functions of the Liver

detoxify many compounds, produced in the body like hydrogen peroxide, alchol many be consumed as part of the diet, drugs may be taken for medical reasons, oxidation or reduction or methylation or combination with another molecule, enxymes that render toxic molecules less toxic, catalase which converts hydrogen peroxide to oygen and water, catalase has a particular high turnover number meaning the nuber of molecules of hydrogen peroxide that one molecule of catalse can render harmless in one minute of five million, conversion of toxic molecules to less  toxic or non-toxic molecules

ethanol, drug that depresses nerve activity, contains chemical potential energy, used for respiration, broken down in the hepatocytes by the action of the enzyme ethanol dehydrogenase, ethanal, dehydrogenated further by the enzyme ethanal dehydrogenase, ethanoate (acetate), combined with coenzyme A to form acetyl coenzyme A, enters the process respirtaion, hydrogen atoms, combined with another coenzyme called NAD to form reduced NAD, required to oxidise and break down the fatty acids for use in respiration, oxidise and break down fatty acids for use in respiration, it has insufficent NAD to deal with the fatty acids, converted back to lipids and are stored in hepatocytes causing the liver to become enlarged, fatty liver which can lead to alchol related hepatitis or to cirrhosis

12 of 30

The Kidney

How many kidneys do most people have? Where are they poisitoned? What supplies each kidney with blood? And drained by? What is the role of the kidney? What does the urine pass out of the kidney down? To where? what happens there? And then? In longitudinal section what is the outer region called? inner region? Whats in the centre? What does it lead to? What surrounds it? Label the kidney?

Whats the bulk of each kidney? How many in each kidney? What are they similar to? Where does each nephron start? What do the capillaries form in the cortex? Called? what is the glomerulus? what is it surrounded by? Called? what is pushed into the bowmans capsule? By which process? Where does the capsule lead? What four parts is that divided into? What happens as the fluid moves along the nephron? What is this achieved by? what do substances do? what is the final product in the collecting duct? Where does this pass? And down the what? To where? what is selective reabsorbition?

How is the fluid altered in the proximal convoluted tuble? What percent is reabsorbed here? Where does the water decrease? By the addition of what and the removal of what? Where does the water potential increase? Why? What happens to the water potential in the collecting duct? Why? What dosw this ensure? What does this mean theres a higher concentration of?

13 of 30

The Kidney

two, on each side of the spine just below the lowest rib, from a renal artery and is drained by a renal vein, to remove waste products from the blood and to produce urine, to remove waste products from the blood and produce urine, the ureter to the bladder where it can be stored before release, the coretx, medulla, is the pelvis which leads into the ureter,

consists of tiny tubles called nephrons, one million in each kidney, tiny blood capillaries, in the cortex, a knot called the glomerulus, a fine network of capillaries that increase the local blood pressure to squeeze fluid out of the blood it is surrounded by a cup or funneled shaped capsule which collects the fluid and leads into the nephron, a cup-shaped structure called the Bowmans capsule, fluid from the blood, ultrafiltration, into the nephron, proximal convuluted tuble distal convoluted tuble loop of henle and the collecting duct, its composition is altered, selective reabsorption, reabsorbed back into the tissue fluid and blood capallaries surrounding the nephron tubule, urine, into the pelvis and down the ureter to the bladder, where useful substances are reabsored from the nephron into the bloodstream while other excretory subsatnces remain in the nephron

by the reabsorption of all the sugars most salts and some water, 85%, descending limb of the loop of henle by the additon of salts and the removal of water, in the ascending limb as salts are removed by active  transport, decreasded again by the removal of water, the final product (urine) has a low water potential, urine has a higher concentration of solutes than is found in the blood and tissue fluid

14 of 30

Formation of Urine

Where does blood flow into the glomerulus from? What do all organs have? What do they do? whats the afferent wider than? What does this do? what does the difference in diameter ensure? Where is the pressure higher the glomerulus or the bowmans capsule? what does this pressure difference cause? where is their a barrier? What does it consist of? name them? What does the endothelium of the capillary have? Why? What does the basement membrane consist of? what do these act as? Against what? What does this mean is held where? what are the epithelial cells of bowmans capsule called? whats their shape? What do podocyttes have many of? called? what do they ensure? What can pass between them? Into where?

What does blood plasma contain? What pushes it? From where? into wehere? What substances does it contain 5?

What is left in the capillary? What does the presecence of proteins mean? What dose this low water potential ensure? What does the fluid contain? Why is the very low water potential of the blood in the capillaires important at what stage? Whats the total volume fluid filtered by both kidneys? What is that a day? Whats it important we do then?

15 of 30

Formation of Urine

afferent arteriole, afferent vessels, they bring blood into the organ, efferent, carries blood away from the glomerulus, that the blood in the capallaries of the glomerulus is under increased pressure, higher in glomerulus than bowmans capsule, to push fluid from the blood into the bowmans capsule that surrounds the glomerulus, between the blood in the capillary and the lumen of the bowmans capsule, three layers, endothelium of the capilary and a basement membrane and the epithelial cells of the bowmans capsule, adapted to allow ultrafiltration, narrow gaps between its cells that blood plasma and the subsatnces dissolved in it can pass through, of a fine mesh of collagen fibres and glycoproteins which act as a filter to prevent the passage of molecules with a relative moelcular mass of greater than 69000, proteins and all blood cells are held in the capalaries of the glomerulus, podocytes, specilaised shape, finger like projections called major processess, that there are gaps between the cells, fluid from the blood in the glomerulus can pass between these cells into the lumen of the bowmans capsule,

dissolved substances, under pressure from the capillary into the lumen of the bowmans capsule, water amino acids glucose urea and inorgaic ions like sodium chlrodie potassium,

blood cells and proteins, that the blood has a very low and negative water potential, that some of the fluid is retained in the blood, some of the water and dissolved substances listed above, to help reabsorb water water at a later stage, 125cm3, 180,dm, we must reabsorb water

16 of 30

Formation of Urine

What happes as fluid moves along the nephron? Reabsorbed where? where does mot reabsorption occur? How much filtrate is reabsorbed? All of what are reabsorbed? Some of what? How is reabsorption achieved through numerous of? what cells in what lining are specisliased to achieve what? What is the cell surface membrane in contact with the tuble fluid like? Forming? What does this increase? What does this membrane also contain? What do they do? in association with what? From where to where? what is this called? what is the opposite membrane close to? What is it also? Increasing? What does this membrane contain? What do they do? what does the cell cytoplasm have many? What does this indicate? Why?

What do the sodium-potassium pumps remove? From where? what dose this reduce? Where are sodium ions transported? Along with what? Via what? What rises in the cell? What are they able to do now? How may this process be enhanced? what happens in the tissue fluid? What does reabsorption of salts glucose and amino acids reduce? And increase? What does this mean will happen? Give an example of a larger molecule? Where may they have entered? How will they be reabsorbed?

17 of 30

Formation of Urine

subsatnces are removed from the fluid and reabsorbed iinto the blood, the proximal convuluted tuble, 85% of the filtrate is reabsorbed, glucose and amino acids and some salts are reabsorbed with some water, combination of processes, linign the proximal convoluted tubule are specialised to achieve this reabsorption, highly folded toform microvili, surface area for reabsorption, special co-transporter proteins, transport glucose or amino acids, sodium ions, from the tubule into the cell, faciliated diffusion, tissue fluid and blood capillaries, also folded to increase surface area, sodium-potassium pumps that pump sodium ions out of the cell and potassium ions into the cell, mitochodria, that an active or energy requiring process is involed as many mitochondria will produce a lot of ATP

sodium ions from the cells lining the proximal convuluted tubule, reduces the concnetration of sodium ions in the celll cytoplasm, into the cell along with glucose or amino acid molecules by facilitated diffusion, glucose and amino acids concnetrations, these substances are able to diffuse out of the opposite side of the cell into the tissue fluid, by active removal of glucose ad amino acids from the cell, these substances diffuse into the blood and are carried away, water potential in the cells and increase water potential in the tubule fuid, water will enter the cells and be reeabsored into the blood by osmosis, larger molecules such as proteins that may have entered the tubule will be reasbrobed by endocytosis

18 of 30

Water Reabsorption

How much fluid is fiktered from the blood and enters the nephron tubules each minute? How much fluid is left after selectrive reabsorption in the proximal convoluted tubule? What is the role of the lopp of henle? What does this ensure?

What does the loop of henle consist of? descends into where? what does it also hace? Back into where? what does the arrangement of the loop of henle allow? What is the overall effect? Consequently where do they diffuse out of? making the water potential where what?

As the fluid in the tuble descends into the medulla what happens to its water potential? give two reasons why? What happens as the fuid ascends bak up towards the cortex? What happens at the base of the tuble? What happens higher up the tuble? What is the wall of the acesnidng limb like? What cant water do? what does the fluid lose as it moves up? What doesn’t it lose?  What is the arrangement of the loop of henle known as? What is the overall effect of this arrangement? What does this cause a build up of? where? what does the movement of salts from the asceding limb into the medualla create high? Where? What is there low then? What does the water potential become increasingly deeper in the medulla? Why is the urine diliute at the top of the acesnding limb? What can water then do? where? what does the amount of water reabsorbed depend on? What is the kidney also an organ of? what is a hhairpin countercurrent multiplier? What is osmoregulation?

19 of 30

Water Reabsorption

125cm3, 45cm3, is to create a low very negative water potential in the tissue of the medulla, that even more water can be reabsorbed from the fluid in the collecting duct

decending limb, into the medulla and an acesnign limb that ascends back out to the cortex, allows salts (sodium chlrodie ions) to be transferredd from the ascending limb to the decsending limb, is to increase the concentration of salts in the tubule fluid, they diffuse out out from the thin-walled ascending limb into the surrounding medulla tissue, the tissue fluid in the medulla a very low very negative water potential

its water potential becomes lower more negative, loss of water by osmosis to the surrounding tissue fluid and the diffusion of sodium and chlroide ions into the tuble from the surrounding tissue fluid, its water potetial becomes higher and less negative, sodium and chlroide ions diffuse out of the tubule into the tissue fluid, sodium and chloride ions are actively transported out into the tissue, particulary at the top is impermeable to water so it cannot leave the tubule, fluid loses salt but not water as it moves up the ascending limb, a hairpin countercurrent multiplier- the arrangemnt of a tubule in a sharp hairpin so that one part of the tubule comes in close contatc with another with the fluid dlowing in opossite directions allowing the exchange between the contents and be used to create a very high convnetration of solutes, to increase the efficency of salt transfer from the acesdening limb to the decseding,. casuing a build up of salt concentration in the surrounding tissue fluid, creates a highsalt cntration in the tissue fluid of the medulla, a very low and negative water potential, increasingly negative deeper into the medulla, the removal of ions from the ascending limb, may be reabsorbed from the urine in the distal convuluted tuubule and collecting ducts, on the needs of the body osmoregulation

20 of 30

Water Reabsorption

At the top of the asceding limb what does the tuble fluid pass along? What is used here? To adjust what? From here where does the fluid flow? At this stage what does the tuble fluid contain a lot of? what does it have high then? Where does the collecting duct carry the fluid? What does the tissue fluid in the medulla have  low of? when does it become even lower? What happens as the tubule fluid passes down the collecting duct? Via? Where does it enter? Via? What happens to it then? what dose the amount of water reabsoirbed depnd on? How much fluid reaches the pelvis each day? Whats the water potential by the time it reaches the pelvis? What about the concentration of urea and salts? Higher than what?

21 of 30

Water Reabsorption

distal convuluted tuble, active transport, the concentrations of various salts, flows into the collecting duct, lot of water, high water potential, low water potential, lower deeper into the medlla, water moves from the tubule into the surrounding tissue by osmosis, enters the blood capillaries by osmosis and is carried away, permeability of the walls of the collecting duct, 1.5-2.0dm (urine), low and negative water poential and the concetration of urea and salts in urine is higher than that of the blood plasma

22 of 30


What is osmoregulation? To prevent problems with osmosis what must be maintained? What three sources is water gained from? What four ways are water lost? If it’s a cool day and you drink a lot of water wha twill you produce? what about a hot day and you’ve drunk very little watter? Is controlling the loss of water In urine the only part of osmregulation processes? What can the walls of the collecting duct be made? According to what though? What do you need on a cool day? What are the walls of the collecting duct then? what does this mean happens? Whats more produced? What do you need a on a hot day? What are the walls? What happens more? What is less produced?

What do the walls of the collecting duct respond to? Where is it? What do cells in the wall have? What does the ADH do? causes what? What is the end result of these reactions? What do these vesicles contain? What are they called? what does this make the cell wal become? What if there is more ADH in the blood? What does this allow more? Via? Where? what passes out of the body? What if there is less ADH in the blood? What does this make? Less what is reabsorbed? Via? Into? What does water do? what releases ADH? What does it act on? Where? increase what?

23 of 30


control of water levels and salt levels in the body, the water balance between cells and the surroudning fluids, food drink and metabolism e.g. respiration, urine sweat water vapur in exhaled air and faeces, a large volume of dilute urine, smaller volumes of concentrated urine, just one part, more or less permeable according to the needs of the body, conserve water, less permeable, less water is reabsorbed and more urine is produced, conserve more water, are made more permeable so that more water can be reabsorbed into the blood, produce smaller volume of urine,

the level of antidiuretic hormone (ADH) in the blood, cells in the collecting duct wall have membrane-bound receptors for ADH, binds to these receptors and causes a chaiin of enzyme-controllde reactions inside the cell, is to insert vesicles containing water-permeable channels (aquaporins) into the cell surface membrane, more permeable to water, more water-permeable channels are inserted, more water to be reabsorbed by osmosis into the blood,smaller volume of urine which has a lower water potential passes out of the body, then the cell surface membrane folds inwards to create new vesicles that remove water-permeable channels from the membrane, less permeable and less water is resabsorbed by osmosis into the blood, more water passes out and is more diluted urine, from the pituatiry gland and acts on the collecitng ductsin the kidneys to increrase their reabsorption of water

24 of 30


What is water potential of the blood monitored by? what if the blood has a lower water potential? what does this stimulate? Where are osmorecptors? What do these cells probably resoond to? What  happens when the water potential of the blood is low? Via? What dose this cause themk to do? stimulating? Where? what is the hypothalamus? What are neurosecretory cells? What do they produce and release? Where is the ADH manufactured? Where does it liee? Where does ADH flow? To where? in the what? What does it do there? What happens if a neurosecretary cell is stimulated? What does that cause? where does the ADh enter? Where are they running through? Where is it transported? What cells does it act on? What are they called then? what happens once the water potential of the blood rises again? How long does it take for ADH to break down? What does it have a half life of? whats a half life? Therefore what happens to it in the blood? What happens to the collecting duct?

what detects an increase in water potential of the blood above the normal level? what happens? what happens next? wha happens next? what decreases? what happens if it decreases lower than normal? etc.?

25 of 30


osmoreceptors in the hypothalamus of the brain, then water water is moved out of the osmorecptor cells by osmosis casusing them to shrink this causes stimulation of the neurosecretory cells, the effects of osmosis, the osmoreceptors cells lose water by osmosis, causes them to shrink and stimulate neurosecretory cells in the hypothalamus, are specialised neurones (nervve cells) that produce and release ADH, manfactured in the cell body of these cells which lies in the hypothalamus, down the axon to the terminal bulb in the posterior pituitary gland, sotred until needed, they send an action potentials down their axons and cause the release of ADH, enters the blood capillaries running through the posterior pituitary glad, around the body and acts on the cells of the collecitng ducts (target cells), less ADH is released, slwoly broken down, half life of 20minutes, of a substance is the time taken for itsconcentration to drop to half its orginal value, present in the blod is broken down and the colelcitng ducts will recieve less stimulation

26 of 30

Kidney Failure

Name the three most common causes of kidney failure? What cant happen if the kidneys fail? What are these waste products? What cant be regulated? What will this lead to?

What are the two main treatments for kidney failure? What does dialysis remove? How? What is the dialysis membrane like? What does it allow? Between what? What does this fluid contain? What happens to any substances in excess? What about any substances in low concentration? What must a person on dialysis also have ? whats the second type of dialysis? Where is the blood passed? What does the moachine contain? Why is heparin added? What is removed? How often is haemodialysis? For how long? What could a patient learn? Whats the third type of dislaysis? What? What does it fill the psace between? What happens after several hours? How often is PD performed? Why is it sometimes called ambulatory PD?

In a kidney transplant what happens to the old kidneys? When would they be moved? Who can be a donor? Is a kidney transplant a small surgerery? What does the patient go under? Where does the surgon implant the new kidney? And attaches it where? how long does it take to feel better? Why pick a kidney transplant? What will the paitents immune system recognise the new kidney as? What will it do? what are pateints given? To help prevent? Nme five advanatges and five disadvantges to kidney transplant?

27 of 30

Kidney Failure

Diabetes mellitus (both type and type 2 sugar diabtes) hypetension or infection, unale to remove excess water and certain waste products, urea and excess salts, levls of water and salts,death

Dialysis or transport, excess wasts like fluid and salt from the blood, passing the blood over a dialysis membrane, partially permeable membrane, exchange of substances between the blood and dialysis fluid, correct concentrations of salts urea water and other substances in the plasma, diffuse across the membrane into the diaylsis fluid, diffuse into the blood from the diaylsis fluid, monitored diet, haemodialysis, blood passes into a machine that contains an artifical dialysis membrane, to avoid clotting and nay bubbles are remved before the blood retursn to the body, at a clinic three times a week for several hours, home, peritoneal dialysis, the filter is the bodys own abdominal membrnae (peritoneum), a surgeon implants a permant tube in the abdomen, dialysis soloution is poured through the tube and fills the space between the abdominal walls and organs, the used soloution is drained from the abdomen, performed in severl consectuivte sesions daily at home or work, as the patient cant walk around having dialysis

left in place, if they were to cause infection or be cancerous, from a living relative who will donate a healthy kidney or from someone who has died, major surgery, anaesthesia, into the lower abdomen and atatches it to eh blood supply and bladder, immediatly, transplant is the best life-extending treatment for kidney failure, as foreign object and produce a reaction, immunosupressant drugs to help prevent infection, Advtanges- freedom from time consuming dialysis, diet is less limited, feeling better physically, a better quality of life like able to travel, no longer seeing oneself as chornically 2, Disavtanges- need immunosupressanrs for the life of the kidney, need major surgery under a general anesthetic, risk of surger inlucde infection blleding and dame surrounding orgas, frequent doctor check ups for organ rejection, side effects like anti rejection

28 of 30

Kidney Failure

What molecules can enter the nephron? What can metabolic product or other substances in the blood do? as long as what? What happens if they are not reabsorbed down the nephron? What does a human embryo start secreting once implaneted in the uterine lining? What is hcg size? What sort of protein? Whats its molecular mass? How early can it be detected in urine? What are pregnancy tests on the market manufactured with? Why are they identical? What is the antibody describe as? Why? How do you take a pregnancy test? What does the hcg attach to? Whats that tagged with? What is formed? Where does it move? Until? whats the result? What is there always? What does a second do?

What do anaboical steroids increase? What are anabolical steroids? What does this increase result in? especially where? why are non-medical uses for anabolical steroids controversial? Where are they banned? Whats anabolic steroids half life? How long do they remain in the blood? Describe their size? Where can they enter then? what does testing for them require? Using what? Or? What is gas chromatography? What is a chromatogram? What happens to the sample in gas chromatography? In the presence of what? Passed along what? Whats the tube lined with? What does each substance do differety? What does it do that’s unique? Whats this time? What happens eventually? What is this then analysed to produce? what two things are run to idenifty and quantify in the chromatograms?

29 of 30

Kidney Failure

substances or molecules with a relative molecular mass of less than 69,000, passed into the urine, long as its small enough, they can be detcected in the urine, human embryo starts secreting a preganncy hormone called human chronic gonadotrophin(hcG), small glycoprotein, 36700, found in urine as early as 6days after conception, monoclonal antibodies, specific it will bind only to hcg not other hormones, soaks a ortion of the test strip in her urine, to an antibody which is tagged witha  blue bead, hcg-antibody complex, moves up the strip until it sticks to a band of immoblised anitibodeis, carryinga  blue bead and attached to hcg are held in one place forming a blue line, control blue line to use for comaprison a second blue line indicates pregnancy

protien syntesis in cells, build-up of cell tissue especially the muscles, controversial because they ca give advtanges in competiive sprots and can have dangerous side effects, banned by all major sporting bodies, half life of 16hours and remain in the blood for many days, smallm molcules and can enter the nephron, invlovles naalysing a urine smaple in a laboratory using gas chromatography or mass spectrometry, sample is vaporisd in the precsne of a gaseous solvent which passes down a long tube lined by an absorption agent, each subsatnce dissolves differently in the gas and staus for a unique specific time, rentetion tinme, the subsatcens comes out of the gas and is absorbed into the lining, analused to create chromatogram, standard sample drugsas well as urine samples are run so that drugs can be identifed and quntified in the chromatograms

30 of 30


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Human, animal and plant physiology resources »