Component 3 - Topic 3.1 - Homeostasis & the Kidney Flashcards
(18 cards)
The kidney:
a) The kidney has 2 Major Functions
1. Excretion =
2. Osmoregulation =
a) The kidney has 2 Major Functions
1. Excretion = the removal of nitrogenous metabolic waste from the body.
2. Osmoregulation = the control of the water potential of the body’s fluids by regulating water CONTENT, and therefore solute concentration.
The Kidney - Production of UREA:
a) Dietary protein is digested and turned into _______ _______. The _______ ________ are transported to the ________ and then around the body, where they are then assimilated into ___________. _________ amino acids are DEAMINATED. Deaminated is a biological term referring to the removal of the _______ ________ from the amino acid. The amine group is then converted into _______. Other nitrogen containing waste is also converted into urea. Urea enters the blood-stream and is removed by the kidneys as ________.
a) Dietary protein is figested and turned into AMINO ACIDS. The amino acids are transported to the LIVER and then around the body, where they are then assimilated into PROTEINS. Excess amino acids are DEAMINATED. Deaminated is a biological term referring to the removal of the amine group from the amino acid. The amine group is then converted into UREA. Other nitrogen containing waste is also converted into urea. Urea enters the blood-stream and is removed by the kidneys as URINE.
The Kidney - STRUCTURE of the Kidney:
a) There are 2 KIDNEYS, describe their location - what is it in relation to - think about the formal word describing the spinal cord?
b) Each kidney is supplied with blood from a ______ ________. Blood then exits back into _________ circulation via the ________ _________. The blood from the _________ _________ is what is filtered.
c) A nephron is a WHAT?
d) Blood enters the nephron via the __________ ___________. The __________ __________ then divides into finer ____________ that comprise the glomerulus. The ______________ is encapsulated by the Bowman’s _________. Blood then leaves the glomerulus via the __________ arteriole. From the __________ arteiole the blood moves through the capillary network that surrounds the _ _ _. From there it then moves into the _______ _______, a capillary network that surrounds the ______ __ ________.
a) There are two kidneys that are found either side of the vetebral column.
b) Each kidney is supplied with blood from a RENAL ARTERY. Blood then exits back into general circulation via the RENAL VEIN. The blood from the RENAL ARTERY is what is filtered.
c) A nephron is an individual blood-filtering units.
d) Blood enters the nephron via the afferent arteriole. The afferent arteiole then divides into finer capillaries that comprise the glomerulus. The glomerulus is encapsulated by the Bowman’s capsule. Blood then leaves the glomerulus via the efferent arteriole. From the afferent arteiole the blood moves through the capillary entwrok that surrounds the PCT. From there is then moves into the VASA RECTA, a capillary network that surrounds the LOOP OF HENLE.
Ultrafiltration - The Bownman’s Capsule:
a)Blood arrives in the capillaries of the glomerulus from the _________ __________. It has a HIGH ______________ pressure because the ___________ arteriole has a WIDER diameter in comparison to the ____________. Furthermore, the heart’s contraction __________ the pressure of the arterial blood. The blood enetering the glomerulus is seperated from the space inside the ___________ _________. This is key. It is speperated by THREE layers.
1. The wall of the __________ surrounding the ________ itself - the wall is ______ cell (that form the ______thelieum thick with pores called ___________ in between the cells.
2. The ____________ ____________ upon which the capillary wall ______ on. It’s an extraceullar layer of __________, mainly collargen and glyco-__________. It acts like a _______ but for certain molecules. Therefore, the _____________ ___________ is described as a _____________ barrier.
3. The wall of the _____________ ___________ is made of epithelial cells called ____________. ____________ have ____________ that extrude out from the main body and they ________ themselves around the ____________ of the glomerulus. These protrusions are called __________. ___________ have slits called filtration slits.
The high blood pressure slams the blood across the capillary walls forcing the solutes and water to leave through the of the capillares, through the basement membrane and then through the filtration slits of the pedicels. Past the cavity they then enter the BOWMAN’s capsule. Filtration under high pressure is called ________________.
b) Glomerular filtrate:
1.
2.
3.
4.
5.
a) Blood arrives in the capillaries of the glomerulus from the afferent arteriole. It has a HIGH HYDROSTATIC pressure because the afferent arteriole has a WIDER diameter in comparison to the EFFERENT. Furthermore, the heart’s contraction increases the pressure of the arterial blood. The blood enetering the glomerulus is seperated from the space inside the BOWMAN’s capsule. This is key. It is speperated by THREE layers.
1. The wall of the capillary surrounding the blood - the wall is one cell (that form the ENDOthelieum thick with pores called FENESRTAE in between the cells.
2. The BASEMENT membrane upon which the capillary wall sits on. It’s an extraceullar layer of proteins, mainly collargen and glycoproteins. It acts like a sieve but for certain molecules. Therefore, the basemetn membrane is a selective barrier.
3. The wall of the BOWMAN’s capsule is made of epithelial cells called PODOCYTES. Podocytes have protrusions that extrude out from the main body and they wrap themselves around the capillaries of the glomerulus. These protrusions are called pedicels. Pedicels have slits called filtration slits.
The high blood pressure slams the blood across the capillary walls forcing the solutes and water to leave through the fenestrae of the capillares, thorugh the basement membrane and then thorugh the filtration slits of the pedicels. Past the cavity they then enter the BOWMAN’s capsule. Filtration under high pressure is called ULTRAFILTRATION.
b) Glomerular filtrate:
1. Water
2. Urea
3. Gluecose
4. Salts
5. Amino acids
The Kidneys - Ultrafiltration Continued:
a) What is the relative water potenital of the of the blood flowing thorugh the efferent arteriole?
a) LOW
Selective Reabsorbtion:
a) The glomerular filtrate contains _________ that the body ELIMINATES. However, it does contain important _______ molecules and ions the body requires and can’t get rid of. This includes _________, ________ ________, ___ ions and ____ ions. Selective reabsorbtion is the process by which useful products are reabsorbed ______ into the blood, as the filtrate flows through the nephron.
b) Selective reabsorbtion is the uptake of specific __________ and ______ from the ____________ filtrate in the nephron back into the bloodstream.
c) The PCT is the ____________ CONVOLUTED TUBULE is the widest and longest region of the NEPHRON. It carries the filtrate away from the Bownman’s capsule. The blood in the capillaries that SURROUND the PCT REABSORBS the VITAL contents that are within the _____. This includes the gluecose and amino acids. This also includes SOME ______(NOT all), _________ , _____ and ______ ions from the filtrate in the proximal convoluted tubule. The PCT has:
1. A large _______ ________ because it’s _______.
2. Cuboidal EPITHELIAL cells that possess ______ ________ on the surface. The __________ face the __________ of the PCT, this is key to recall. On the outside, facing the capillaries, the cuboidal eptihelial cells have invaginations called ________ channels (think of _________leaves being in here).
3. Many ______________ exist in these cells. Why? for ____ synthesis that funds active transport.
4. The PCT is tightly associated with the ____________.
5. _______ ____________ between cells of the PCT. These t______ j_________ hold adjacent cells very close to one another. The purpose of this is that it prevents molecules from diffusing BETWEEN adjacent cells or from the back into the glomerular filtrate.
a) The glomerular filtrate contains wastes that the body ELIMINATES. However, it does contain important useful molecules and ions the body requires and can’t get rid of. This includes gluecose, amino acids, sodium ions and chloride ions. Selective reabsorbtion is the process by which useful products are reabsorbed back into the blood, as the filtrate flows through the nephron.
b) Selective reabsorbtion is the uptake of specific molecules and ions from the glomerular filtrate in the nephron back into the bloodstream.
c) The PCT is the PROXIMAL CONVOLUTED TUBULE is the widest and longest region of the NEPHRON. It carries the filtrate away from the Bownman’s capsule. The blood in the capillaries that SURROUND the PCT REABSORBS the VITAL contents that are within the PCT. This includes the gluecose and amino acids. This also includes SOME urea (NOT all), water, Na+ and Cl- ions from the filtrate in the proximal convoluted tubule. The PCT has:
1. A large SA because it’s LONG.
2. Cuboidal EPITHELIAL cells that possess micro-villi on the SA. The Microvilli face the LUMEN of the PCT this is key to recall. On the outside, facing the capillaries, the cuboidal eptihelial cells have invaginations called BASAL channels (think of basal leaves being in here).
3. Many mitochondria exist in these cells. Why? for ATP synthesis that funds active transport.
4. The PCT is tightly associated with the capillaries.
5. Tight junctions between cells of the PCT. These tight junctions hold adjacent cells very close to one another. The purpose of this is that it prevents molecules from diffusing BETWEEN adjacent cells or from the back into the glomerular filtrate.
Selective Reabsorbtion - PCT:
a) About 70% of the salts in the filtrate are reabsorbed to the blood. Some reabsorbtion is _________, although most uses ACTIVE ___________ by membrane ________ that exist.
b) All the gluecose in the PCT and amino acids are reabsorbed via____-_____________ with ______ ions. The gluecose and amino acids and TWO ____ions bind to a ___________ protein in the ________ epitheliam membrane. They then enter by _________ across. The gluecose and amino acids enter the capillary via ____________ diffusion. The _____ ions meanwhile are __________ into the capillary, reducing their concentration in the epithelial cell below that of the __________. As a result, more ______ ions enter the cell, bringing with them amino acids and gluecose. This entry is called ____________Y ACTIVE TRANSPORT- the coupling of movement e.g of NA+ down their _______________ gradient with the movement of e.g gluecose. It doesn’t utilise ATP directly, but it uses energy from the ______________ gradient of Na+ ions from the lumen into the cell, which was generated by the active transport of Na+ ions from the epithelial cells into the capillary.
c) About 90% of the water in the glomerular filtrate is reabsorbed to the blood passively, by osmosis, WHY? Link to the ions who are moving in before the water…
d) About 50% if the UREA and smaller proteins in the glomerular filtrate is REABSORBED back to the blood by diffusion. WHY? Think about the water’s effect. The water leaves and so the relative conc. of the urea in the PCT is WHAT relative to that of the WHAT? This causes? That’s why 50% is reabsorbed…
a) About 70% of the salts in the filtrate are reabsorbed to the blood. Some reabsorbtion is PASSIVE, although most uses ACTIVE TRANSPORT by membrane pumps that exist.
b) All the gluecose in the PCT and amino acids are reabsorbed via CO-Transport with Na+ ions. The gluecose and amino acids and TWO Na+ ions bidn to a transporter protein in the cuboidal epitheliam membrane. They then enter ad diffuse across. The gluecose and amino acids enter the capillary via facillitated diffusion. The Na+ ions meanwhile are PUMPED into the capillary, reducing their concentration in the epithelial cell below that of the LUMEN. As a result, more Na+ ions enter the cell, bringing with them amino acids and gluecose. This entry is called SECONDARY ACTIVE TRANSPORT- the coupling of movement e.g of NA+ down their electrochemical gradient with the movement of e.g gluecose. It doesn’t utilise ATP directly, but it uses energy from the electrochemical gradien tof Na+ ions from the lumen into the cell, which was generated by the active transport of Na+ ions from the epithelial cells into the capillary.
c) About 90% of the water in the glomerular filtrate is reabsorbed to the blood passively, by osmosis, as reasbsorbed ions lower the water potential of the blood (REabsorbtion of Na+ ions to name but a few).
d) About 50% if the UREA and smaller proteins in the glomerular filtrate is REABSORBED back to the blood by diffusion. SO much water has been lost from the filtrate that their relative concentration in the PCT is HIGH. So this causes them to diffuse down their concentration gradient INTO the blood.
The Gluecose Threshold:
a) Gluecose is an energy source and the body would be disadvantaged if it were lost. Under normal circumstances, the PCT reabsorbs all the gluecose that is present in the glomerular filtrate. If the concentration of gluecose in the filtrate is TOO high however this may result in too few ___________ __________ molecules in the membrane of the PCT cells being able to __________ them all! Gluecose would then pass through the _______ ___ ________ and into the _______.
b) Hyperglycaemia = very HIGH gluecose ______________ the blood. high conc. remains in the glomerular filtrate and as a result _________ _________ from leaving and being reabsorbed. As a result this can cause HIGH ______ output. High blood gluecose and dehydration leads to _______.
a) Gluecose is an energy source and the body would be disadvantaged if it were lost. Under normal circumstances, the PCT reabsorbs all the gluecose that is present in the glomerular filtrate. If the concentration of gluecose in the filtrate is TOO high however this may result in too few transport protein molecules in the membrane of the PCT cells being able to reabsorb them all! Gluecose would then pass through the loop of henle and into the urine.
b) Hyperglycaemia = very HIGH gluecose thickening the blood. high conc. remains in the glomerular filtrate and as a result prevents water from leaving and being reabsorbed. As a result this can cause HIGH urine output. High blood gluecose and dehydration leads to COMA.
The Reabsorbtion of Water:
a) A major challenge for terrestrial organisms - arguably the most notable - is the need for conserving WATER. The body can’t afford to LOSE large amount - therefore, like explianed earlier, high gluecose content in the blood can be fatal, reabsorbtion is stopped. Roughly 90% of water is filtered at the PCT. Some of the remiander (the 10%) is then reabsorbed back into the blood at the DCT, in the CORTEX and from the Loop of Henle in the medulla. About 5% is reabsorbed from the collecting duct.
Now, the biology book explains how the PCT and collecting ducts have very ‘sterotyped’ functions (i.e. by stereotyped, we mean that when we talk about the PCT and water absorbtion we always associate it with the value 90% for water absorbtion and 5% for the Collecting DUCT. In truth however, this isn’t correct. In fact, the DCT and collecting duct both have varying abilites when it comes to reabsorbtion of water. The variability depends on osmoreceptors who detect whether more or less water should be absobed. Therefore, the DCT and collecting tube act as the FINE control of the body’s water content.
a) A major challenge for terrestrial organisms - arguably the most notable - is the need for conserving WATER. The body can’t afford to LOSE large amount - therefore, like explianed earlier, high gluecose content in the blood can be fatal, reabsorbtion is stopped. Roughly 90% of water is filtered at the PCT. Some of the remiander (the 10%) is then reabsorbed back into the blood at the DCT, in the CORTEX and from the Loop of Henle in the medulla. About 5% is reabsorbed from the collecting duct.
Now, the biology book explains how the PCT and collecting ducts have very ‘sterotyped’ functions (i.e. by stereotyped, we mean that when we talk about the PCT and water absorbtion we always associate it with the value 90% for water absorbtion and 5% for the Collecting DUCT. In truth however, this isn’t correct. In fact, the DCT and collecting duct both have varying abilites when it comes to reabsorbtion of water. The variability depends on osmoreceptors who detect whether more or less water should be absobed. Therefore, the DCT and collecting tube act as the FINE control of the body’s water content.
The Reabsorbtion of Water:
a) The mechanisms of water reabsorbtion - The filtrate enters the DESCENDING LIMB of the loop of henle and moves to the HAIRPIN BEND and up into the ASCENDING LIMB.
b) The walls of the ascending limb are IMPERMEABLE to water. They actively transport Na+ and Cl- ions OUT into the medulla into the tissue fluid present. A longer loop of henle means more IONS are exported into the medulla. The loop of henle collectively concentrate salts in the tissue fluid, which therefore has a LOW water potential. As the filtrate climbs from the bottom of the hairpin, it contains PROGRESSIVELY fewer ions. It becomes increasingly dilute and its water potential increases.
The water potential of the descending limb are permeable to water, and slightly permeable to Na+ and Cl- ions.
- As a result as the filtrate flows DOWN the descending limb, water diffuses OUT, by osmosis, into the tissue fluid of the medulla, which has a LOW water potential. From there it moves into the VASA RECTA (the capillaries surrounding the loop of henle).
- At the same time, some Na+ and Cl- ions diffuse INTO the diffuse INTO the loop of henle (remeber firstly, the membrane is permeable to them and also the medulla’s tissue fluid contians a HIGH conc. of these ions relative to the inside of the descending limb).
a) The mechanisms of water reabsorbtion - The filtrate enters the DESCENDING LIMB of the loop of henle and moves to the HAIRPIN BEND and up into the ASCENDING LIMB.
b) The walls of the ascending limb are IMPERMEABLE to water. They actively transport Na+ and Cl- ions OUT into the medulla into the tissue fluid present. A longer loop of henle means more IONS are exported into the medulla. The loop of henle collectively concentrate salts in the tissue fluid, which therefore has a LOW water potential. As the filtrate climbs from the bottom of the hairpin, it contains PROGRESSIVELY fewer ions. It becomes increasingly dilute and its water potential increases.
The water potential of the descending limb are permeable to water, and slightly permeable to Na+ and Cl- ions.
- As a result as the filtrate flows DOWN the descending limb, water diffuses OUT, by osmosis, into the tissue fluid of the medulla, which has a LOW water potential. From there it moves into the VASA RECTA (the capillaries surrounding the loop of henle).
- At the same time, some Na+ and Cl- ions diffuse INTO the diffuse INTO the loop of henle (remeber firstly, the membrane is permeable to them and also the medulla’s tissue fluid contians a HIGH conc. of these ions relative to the inside of the descending limb).
The Reabsorbtion of Water - Continued:
a) As the filtrate flows DOWN the descending limb, it contains progressively LESS water and MORE ions and so, at the bottom of the hairpin, the filtrate is at its most concentrated , with the lowest water potential.
b) Having 2 limbs of the loop of henle running side-by-side, with the fluid flowing down in one and up in the other, enables the maximum concentration to be built up at the APEX of the loop. This mechanism is a counter-current multiplier, because flow in two limbs is in OPPOSING directiona (counter-current) and the concentration of solutes is slowly INCREASING (i.e. being multiplied). The solute conc. is even higher in the MEDULLA.
c) The longer the loop of henle, the lower the water potential in the medulla and the more water leaves the collecting duct by osmosis. The filtrate becomes more concentrated than the blood (hypertonic to the blood).
a) As the filtrate flows DOWN the descending limb, it contains progressively LESS water and MORE ions and so, at the bottom of the hairpin, the filtrate is at its most concentrated , with the lowest water potential.
b) Having 2 limbs of the loop of henle running side-by-side, with the fluid flowing down in one and up in the other, enables the maximum concentration to be built up at the APEX of the loop. This mechanism is a counter-current multiplier, because flow in two limbs is in OPPOSING directiona (counter-current) and the concentration of solutes is slowly INCREASING (i.e. being multiplied). The solute conc. is even higher in the MEDULLA.
c) The longer the loop of henle, the lower the water potential in the medulla and the more water leaves the collecting duct by osmosis. The filtrate becomes more concentrated than the blood (hypertonic to the blood).
Osmoregulation:
a) What is OSMOREUGULATION about? There are two types of entities whose concentrations must be maintained. Name BOTH. Why must they be maintained?
b) How does osmoregulation work? Describe the interaction between the signal sent by the osmoreceptors and the hypothalamus. What happens to the DCT and Collecting Duct?
a) Osmoregulation is the HOMEOSTATIC function that maintains concentrations of ENZYMES and METABOLITES, so that the reactions within cells occur at a constant and appropriate rate.
b) Osmoregulation operates by NEGATIVE feedback. The hypothalamus, at the base of the brain, is the receptor. The hypothalamus recieves signals from osmoreceptors whom monitor the solute potenital of the blood. It’s also the co-ordinator, this is because the hypothalamus signals to the effector, the pituitary gland, to release ADH. This returns the system to normal if it DEVIATES too far, by changing the BEHAVIOUR of the walls of the distal convoluted tubule and the collecting duct.
a) What is ADH?
b) What is DIURESIS? Therefore, what is a DIURETIC - e.g ALCOHOL
c) What might cause the water potential of the blood to fall? 3 things - One is linked to TEMPERATURE.
d) What detects the REDUCTION in water potential? Where is the detector located? Secretory granules carry _____ along axons from the _____________ to the posterior lobe of the pituitary gland, from where _________ is secreted into the __________ ___________. It’s carried to the kidneys WHERE:
1. ________ increases the ________________ of the walls of the _______ and the collecting duct to the water.
2. More water is reabsorbed from there into the region of _______ solute concentration, low water potential in the ____________.
3. More water is reabsorbed from the __________ into the blood in the capillaries.
4. The water potential of the blood is restored to NORMAL.
5. The small volume of urine produced is relatively concentrated now. Its concentration is close to the concentration of the tissues near the _______ of the Loop of Henle, and it is hypertonic to the body fluids. Hypertonic means that a particular solution in question is ________ _____________ in relation to another solution…
a) ADH, antidiuretic hormone is produced by the hypothalamus and is secreted by the POSTERIOR pituitary gland. Once released into the bloodstream it shall make its way to both kidneys. Its job is to alter the behaviour of the DCT and Collecting DUCT by INCREASING their PERMEABILITY to water. This shall allow more water to pass through as a result. The end result is CONCENTRATED URINE.
b) Diuresis is the production of large volumes of water…Diuresis is the product of a diuretic. Alcohol is an example of a diuretic. ANTI-diuretic therefore is the OPPOSITE. It form CONCENTRATED URINE.
c)
1. A fall is water INTAKE, this means that the blood is more concentrated with the solutes already present.
2. HIGH salt intake.
3. Sweating, water is leaving and therefore the relative concentration of the solutes is INCREASING as a result!
d) The OSMORECEPTORS in the HYPOTHALAMUS. Secretory granules carry ADH along axons from the hypothalamus to the posterior lobe of the pituitary gland, from where ADH is secreted into the blood stream. It’s carried to the kidneys WHERE:
1. ADH increases the permeability of the walls of the DCT and the collecting duct to the water.
2. More water is reabsorbed from there into the region of HIGH solute concentration, low water potential in the MEDULLA.
3. More water is reabsorbed from the medulla into the blood in the capillaries.
4. The water potential of the blood is restored to NORMAL.
5. The small volume of urine produced is relatively concentrated now. Its concentration is close to the concentration of the tissues near the apex of the Loop of Henle, and it is hypertonic to the body fluids. Hypertonic means that a particular solution in question is more CONCENTRATED in relation to another solution…
ADH Mechanism:
a) Aquaporins are ____________ MEMBRANE proteins (proteins that span across the entire length of the membrane). These proteins have a _______ through which water molecules move. At least 9 are known to operate in the kidney. The existance of many more types is suspected. In the walls of the DCT tubule and collecting duct:
1. ADH alters the permeability by binding to membrane _____________.
2. _________ cyclase, an enzyme, catalyses the production of cyclic _ _ _ - the 2nd messanger who causes step 3 to occur (i.e ‘calling’ the cytoplasmic vesicles to arrive to the location).
3. Cytoplasmic vesicles containing _____________ move to and _______ with the cell membrane.
4. _____________ are incorporated into the membrane.
5. Water molecules move in single file through their pores into the cell, _______ a water potential gradient.
a) Aquaporins are INTRINSIC MEMBRANE proteins (proteins that span across the entire length of the membrane). These proteins have a pore through which water molecules move. At least 9 are known to operate in the kidney. The existance of many more types is suspected. In the walls of the DCT tubule and collecting duct:
1. ADH alters the permeability by binding to membrane receptors.
2. Adenyl cyclase, an enzyme, catalyses the production of cyclic AMP, the 2nd messanger who causes step 3 to occur (i.e ‘calling’ the cytoplasmic vesicles to arrive to the location).
3. Cytoplasmic vesicles containing aquaporins move to and fuse with the cell membrane.
4. Aquaporins are incorporated into the membrane.
5. Water molecules move in single file through their pores into the cell, down a water potential gradient.
Kidney Failure & Treatment:
a) The major roles of the _________ are excretion and osmoregulation. If they fail, the body is unable to remove ________ from the blood… As a result the ______ concentration remains HIGH - _______ levels are reached. Furthermore, the body is unable to remove excess _______ (due to high _________ concentration) and so bodily fluids ___________ in volume and are diluted, compromising ____________ reactions.
Causes of Kidney Failure:
- Diabetes - High ___________ concentration in the plasma results in the ___________ (the capillaries that form the glomerulus) losing protein especially, ___________, into the filtrate and causing some proteins to LINK together triggering scarring in a condition called glumerulo__________.
a) The major roles of the kidney are excretion and osmoregulation. If they fail, the body is unable to remove UREA from the blood… As a result the UREA concentration remains HIGH - toxic levels are reached. Furthermore, the body is unable to remove excess water (due to high solute concentration) and so bodily fluids increase in volume and are diluted, compromising METABOLIC reactions.
Causes of Kidney Failure:
- Diabetes - High gluecose concentration in the plasma results in the glomeruli (the capillaries that form the glomerulus) losing protein especially, ALBUMIN, into the filtrate and causing some proteins to LINK together triggering scarring in a condition called glumerulosclerosis.
Causes of Kidney Failure:
a)
1. ________ Blood Pressure - Damages the __________, prevents ultrafiltration.
2. Autoimmune Disease - The body makes ___________ against its own tissues.
3. Infection
4. Road Traffic Incident - _________ Injuries
b) The body can remain healthy with just ONE kidney. However, there shall be a loss of kidney function later in life (life span is normal though). If both are comprimised then treatments are put in place to reduce the concentration of the WASTE products and control the volume of body fluids, to regulate solute concentration:
- Reducing intake of certain ___________, in particular ________ of course (To reduce ________ concentration ultimately).
- Using DRUGS to reduce blood pressure:
- Angiotensin-converting __________ (ACE) ___________ and angiotensin __________ blockers (ARBs) reduce the effect of ______________ a hormone that constricts blood _________ to raise blood pressure of the blood within.
- Calcium channel blockers _________ blood vessels and reduce blood pressure.
- _______ blockers reduce the effect of adrenalin, one effect of which is increased blood pressure as the heart rate rises (links to how we use ABRs and ACEs to stop b.p. from rising from within the blood itself). - The concentrations of dissolved _____________ and __________ ions are normally maintained by a balance of absorbtion in the small intestine and by selective reabsorbtion by the nephrons.
- Dialysis - the blood to be cleaned and a dialysis fluid are seperated by a ___________ permeable. The dialysis fluid has the same water potential as healthy blood, but a ______ ion concentration and ____ UREA. Inorganic ions in water & urea __________ out of the blood across membrane, _________ their concentration gradients. The dialysis fluid contains __________ at the normal concentration of the blood so it ensures that none diffuses out of the blood!
- Kidney ____________
a)
1. High Blood Pressure - Damages the glomeruli, prevents ultrafiltration.
2. Autoimmune Disease - The body makes antibodies against its own tissues.
3. Infection
4. Road Traffic Incident - Crushing Injuries
b) The body can remain healthy with just ONE kidney. However, there shall be a loss of kidney function later in life (life span is normal though). If both are comprimised then treatments are put in place to reduce the concentration of the WASTE products and control the volume of body fluids, to regulate solute concentration:
- Reducing intake of certain NUTRIENTS, in particular protein of course (To reduce UREA concentration ultimately).
- Using DRUGS to reduce blood pressure:
- Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) reduce the effect of angiotensin a hormone that constricts blood vessels to raise blood pressure of the blood within.
- Calcium channel blockers dilate blood vessels and reduce blood pressure.
- Beta blockers reduce the effect of adrenalin, one effect of which is increased blood pressure as the heart rate rises (links to how we use ABRs and ACEs to stop b.p. from rising from within the blood itself). - The concentrations of dissolved potassium and calcium ions are normally maintained by a balance of absorbtion in the small intestine and by selective reabsorbtion by the nephrons.
- Dialysis - the blood to be cleaned and a dialysis fluid are seperated by a selective permeable. The dialysis fluid has the same water potential as healthy blood, but a LOW ion concentration and NO UREA. Inorganic ions in water & urea diffuse out of the blood across membrane, down their concentration gradients. The dialysis fluid contains gluecose at the normal concentration of the blood so it ensures that none diffuses out of the blood!
- Kidney Transplant
Haemodialysis:
a) Haemodialysis uses a dialysis machine. Blood is take from an ________, usually from found in the _______. It is then run through ___________ of LONG and NARROW ________ made of ____________ permeable dialysis tubing. The fibres are surrounded by dialysis ________. The _______ in the tubing allow ___________ in solution to move _____ into the dialysis fluid, but NOT ________ proteins. The blood and dialysis fluid run is ____________ directions, enhancing diffusion out of the blood using _________-___________ FLOW. The blood is then returned to the body.
- _________ is added to the blood to prevent ________ occuring - it’s a blood _________!
A sensor in the dialysis fluid detects ________________ that would diffuse through if RBCs are damaged.
a) Haemodialysis uses a dialysis machine. Blood is take from an artery, usually from found in the arm. It is then run through thousands of LONG and NARROW fibres made of selectively permeable dialysis tubing. The fibres are surrounded by dialysis FLUID. The pores in the tubing allow molecules in solution to move OUT into the dialysis fluid, but NOT large proteins. The blood and dialysis fluid run is opposing directions, enhancing diffusion out of the blood using COUNTER-CURRENT FLOW. The blood is then returned to the body.
- Heparin is added to the blood to prevent cloting occuring - it’s a blood thinner!
A sensor in the dialysis fluid detects haemoglobin thta would diffuse through if RBCs are damaged.
a) CAPD - Continuous _______________ ____________ Dialysis (CAPD) - Is ‘ambulatory’ because the patient can _______ and _______, carrying on with normal activities. The patients drain a 1-3 dm3 bag of dialysis fluid through a __________ in the abdomen, into the body cavity. The peritoneum is the membrane lining the body cavity and it has a rich supply of _____________. It (_____________) acts as the dialysis membrane and materials are removed from the blood in the ____________ into the dialysis _________. After about 40 minutes, the fluid is drained from the abdomen, under ________.
a) Continuous Ambulatory Peritoneal Dialysis (CAPD) - Is ‘ambulatory’ because the patient can walk and move, carrying on with normal activities. The patients drain a 1-3 dm3 bag of dialysis fluid through a cathetar in the abdomen, into the body cavity. The peritoneum is the membrane lining the body cavity and it has a rich supply of capillaries. It acts as the dialysis membrane and materials are removed from the blood in the capillaries into the dialysis fluid. After about 40 minutes, the fluid is drained from the abdomen, under gravity.
