AQA A level biology- Osmoregulation
TEST QUESTIONS AND ANSWERS | A
GRADE : GUARANTEED PASS!!!!!
Explain how a lack of insulin affects reabsorption of glucose in the kidneys of a person
who does not secret insulin? - ANSWER-1) High concentration of glucose in blood
2) High concentration in tubule/in filtrate
3) Reabsorbed by (facilitated diffusion/active transport)
4) Requires proteins/carriers
5) These are working at maximum rate (are saturated)
6) Not all glucose is reabsorbed, some is lost in urine
Describe and explain how the secretion of ADH affects urine produced by the kidneys? -
ANSWER-1) Permeability of (membrane/cells) to water is increased
2) More water absorbed (from/leaves) distal tubule/ collecting duct
3) Smaller volume of urine
4) Urine becomes more concentrated
Describe how urea is removed from the blood? - ANSWER-1) Hydrostatic pressure
2) Cause ultrafiltration at (bowman's capsule/glomeruli/renal capsule)
3) Through basement membrane
4) Enabled by small size urea molecule
Label a nephron
Describe how ultrafiltration produces glomerular filtrate? - ANSWER-1) Blood
pressure/hydrostatic pressure
2) Small molecules (named example)
3) Pass through basement membrane (basement membrane acts as a filter)
4) Protein too large to go through (large molecule) so stays behind
5) Presence of pores in capillaries (podocytes=form a filtration barrier)
If the glomerular filtrate of a diabetic person contains a high concentration of glucose,
he produces a larger volume of urine.Explain why? - ANSWER-1) Glucose in filtrate
lowers water potential
2) Lower water potential gradient
3) Less water reabsorbed by osmosis
, Which part of a nephron would have to be damaged to cause proteins from blood
plasma to be present in the urine? Explain your answer - ANSWER-
(Glomerulus/Bowman's capsule/renal capsule);
-Proteins are large molecules therefore can only pass through basement
membrane if filter (BM) is damaged
Describe ways mammals can obtain water? - ANSWER-1) Metabolic water from
respiration;
2) From aerobic respiration (use of oxygen)
Explain why proteins are not normally present in the urine of a healthy person but may
be present in the urine of a person with glomerulosclerosis? - ANSWER-1) Protein
molecules are too large to cross filter in healthy person
2) Proteins can only cross if filter is damaged (protein from damaged glomerulus
enters filtrate)
By what process does urea enter the fluid in the abdominal cavity from the blood? -
ANSWER-By simple diffusion
Explain how the structure of protein molecules allow them to form channels through
which only water can pass through - ANSWER-1) Each protein has a tertiary
structure
2) Gives (specific/correct) (shape/size) to inside of (channel/pore)
Explain how the cells of the collecting duct are able to absorb water from the filtrate
through the protein channels in their plasma membrane? - ANSWER-1) More
(negative/lower) water potential inside tubule cells
2) Water therefore enters via diffusion/osmosis
Which hormone causes the decrease in the water content in the distal convoluted
tubule? - ANSWER-ADH;
(ADH constantly regulates and balances the amount of water in your blood.It tells
your kidneys how much water to conserve.)
Where does ultrafiltration occur? - ANSWER-Renal capsule/Bowman's
capsule/Glomerulus
Give one component of blood which is not normally present in the filtrate - ANSWER-
Blood cells/platelets/proteins/named plasma protein
Explain how the cells of the PCT are adapted for reabsorption of glucose - ANSWER-1)
Many mitochondria=provides ATP (energy) for active transport
2) Many carrier proteins= for active transport
3) Many channel proteins= for facilitated diffusion
4) Microvilli= provides large surface area for reabsorption
5) Specific carriers for specific molecules e.g. sodium
TEST QUESTIONS AND ANSWERS | A
GRADE : GUARANTEED PASS!!!!!
Explain how a lack of insulin affects reabsorption of glucose in the kidneys of a person
who does not secret insulin? - ANSWER-1) High concentration of glucose in blood
2) High concentration in tubule/in filtrate
3) Reabsorbed by (facilitated diffusion/active transport)
4) Requires proteins/carriers
5) These are working at maximum rate (are saturated)
6) Not all glucose is reabsorbed, some is lost in urine
Describe and explain how the secretion of ADH affects urine produced by the kidneys? -
ANSWER-1) Permeability of (membrane/cells) to water is increased
2) More water absorbed (from/leaves) distal tubule/ collecting duct
3) Smaller volume of urine
4) Urine becomes more concentrated
Describe how urea is removed from the blood? - ANSWER-1) Hydrostatic pressure
2) Cause ultrafiltration at (bowman's capsule/glomeruli/renal capsule)
3) Through basement membrane
4) Enabled by small size urea molecule
Label a nephron
Describe how ultrafiltration produces glomerular filtrate? - ANSWER-1) Blood
pressure/hydrostatic pressure
2) Small molecules (named example)
3) Pass through basement membrane (basement membrane acts as a filter)
4) Protein too large to go through (large molecule) so stays behind
5) Presence of pores in capillaries (podocytes=form a filtration barrier)
If the glomerular filtrate of a diabetic person contains a high concentration of glucose,
he produces a larger volume of urine.Explain why? - ANSWER-1) Glucose in filtrate
lowers water potential
2) Lower water potential gradient
3) Less water reabsorbed by osmosis
, Which part of a nephron would have to be damaged to cause proteins from blood
plasma to be present in the urine? Explain your answer - ANSWER-
(Glomerulus/Bowman's capsule/renal capsule);
-Proteins are large molecules therefore can only pass through basement
membrane if filter (BM) is damaged
Describe ways mammals can obtain water? - ANSWER-1) Metabolic water from
respiration;
2) From aerobic respiration (use of oxygen)
Explain why proteins are not normally present in the urine of a healthy person but may
be present in the urine of a person with glomerulosclerosis? - ANSWER-1) Protein
molecules are too large to cross filter in healthy person
2) Proteins can only cross if filter is damaged (protein from damaged glomerulus
enters filtrate)
By what process does urea enter the fluid in the abdominal cavity from the blood? -
ANSWER-By simple diffusion
Explain how the structure of protein molecules allow them to form channels through
which only water can pass through - ANSWER-1) Each protein has a tertiary
structure
2) Gives (specific/correct) (shape/size) to inside of (channel/pore)
Explain how the cells of the collecting duct are able to absorb water from the filtrate
through the protein channels in their plasma membrane? - ANSWER-1) More
(negative/lower) water potential inside tubule cells
2) Water therefore enters via diffusion/osmosis
Which hormone causes the decrease in the water content in the distal convoluted
tubule? - ANSWER-ADH;
(ADH constantly regulates and balances the amount of water in your blood.It tells
your kidneys how much water to conserve.)
Where does ultrafiltration occur? - ANSWER-Renal capsule/Bowman's
capsule/Glomerulus
Give one component of blood which is not normally present in the filtrate - ANSWER-
Blood cells/platelets/proteins/named plasma protein
Explain how the cells of the PCT are adapted for reabsorption of glucose - ANSWER-1)
Many mitochondria=provides ATP (energy) for active transport
2) Many carrier proteins= for active transport
3) Many channel proteins= for facilitated diffusion
4) Microvilli= provides large surface area for reabsorption
5) Specific carriers for specific molecules e.g. sodium
