Physiology Lab Final
Describe two variables that affect the rate of diffusion? ✔✔size of material and concentration
of gradient
Why do you think the Urea was not able to diffuse through the 20MWCO membrane?
✔✔because urea was too big to pass through the 20 MWCO membrane
Describe the result of the attempt to diffuse glucose and albumin through the 200 MWCO
membrane? ✔✔the glucose diffused through the 200MWCO membrane, while there was no
diffusion of albumin.
Put the following in order from the smallest to largest molecular weight: glucose, sodium
chloride, albumin, urea. ✔✔sodium chloride, urea, glucose, albumin
Explain one way in which facilitated diffusion is the same as simple diffusion and one way in
which it differs. ✔✔both are passive diffusion that are from high concentration gradient to a
low concentration gradient. facilitated differs from simple because it requires a carrier protein
to diffuse
The larger value obtained when more glucose carriers were present corresponds to an increase
in the rate of glucose transport. Explain why the rate increased. ✔✔the rate increased because
there is more room and surface area increases relative to glucose
Explain the effects that increasing the NaCl concentration had on osmotic pressure and why it
has this effect. ✔✔Increasing the NaCl will increase the osmotic pressure. because water needs
to diffuse to the higher concentration gradient until equilibrium is reached
Describe one way in which Osmosis is similar to simple diffusion and one way in which it is
different. ✔✔both are passive transports of high concentration gradient to low concentration
gradient. Osmosis differs because it is the diffusion of water from a high to a low concentration
gradient through a selective permeable membrane
the conditions were 9 mM albumin in the left beaker and 10 mM glucose in the right beaker
with the 200 MWCO membrane in place. Explain the results. ✔✔glucose diffuses from right
beaker to the left beaker until equilibrium is reached. albumin can't diffuse through the
membrane and osmotic pressure of 153mmHg results
which solute did not appear in the filtrate using any of the membranes? ✔✔activated charcoal
, why did increasing the pressure increased the filtration rate but not the concentration of
solutes? ✔✔because the pressure allows for more movement through the membrane but
equilibrium was not reached
describe the significance of using 9mM sodium chloride inside the cell and 6 mM potassium
chloride outside the cell, instead of other concentration ratio. ✔✔because the Na/K pump
allows for 3:2 ratio
Explain why there was no sodium transport even though ATP was present. ✔✔in order for
Na/K pump to function both ions need to be present even if ATP is present. since only Na was
present it would use a passive diffusion down the concentration gradient
Explain why the addition of glucose carriers had no effect on sodium or potassium transport.
✔✔because glucose concentration does not affect the Na/K concentration. it only has affect on
glucose itself
do you think glucose is being actively transported or transported by facilitated diffusion in this
experiment? explain you answer. ✔✔it is being transported by facilitated diffusion. since
glucose is a lipid insoluble and too large to pass through the membrane it requires a carrier but
not ATP
Which rat had the fastest basal metabolic rate (BMR)? ✔✔the normal rat
Why did the BMR's differ between the normal rat and the surgically altered rats? ✔✔The other
2 rats had either had the thyroid or pituitary gland surgically removed. This plays an important
part in hormone secretion to raise or lower BMR
If an animal had been thyroidectomized, what hormone(s) would be missing in its blood?
✔✔Thyroxine and Calcitonin
If an animal had been hypophysectomized, what effect(s) would you expect to see in the
hormone levels in its blood and in its BMR? ✔✔The metabolic rate would go down with no
pituitary gland to produce THS
What was the effect of thyroxine injections on the normal rat's BMR? ✔✔he metabolic rate
increased to 2000, which was higher than the baseline
What was the effect of thyroxine injections on the thyroidectomized rat's BMR?
How does the BMR in this case compare with the normal rat's BMR?
Describe two variables that affect the rate of diffusion? ✔✔size of material and concentration
of gradient
Why do you think the Urea was not able to diffuse through the 20MWCO membrane?
✔✔because urea was too big to pass through the 20 MWCO membrane
Describe the result of the attempt to diffuse glucose and albumin through the 200 MWCO
membrane? ✔✔the glucose diffused through the 200MWCO membrane, while there was no
diffusion of albumin.
Put the following in order from the smallest to largest molecular weight: glucose, sodium
chloride, albumin, urea. ✔✔sodium chloride, urea, glucose, albumin
Explain one way in which facilitated diffusion is the same as simple diffusion and one way in
which it differs. ✔✔both are passive diffusion that are from high concentration gradient to a
low concentration gradient. facilitated differs from simple because it requires a carrier protein
to diffuse
The larger value obtained when more glucose carriers were present corresponds to an increase
in the rate of glucose transport. Explain why the rate increased. ✔✔the rate increased because
there is more room and surface area increases relative to glucose
Explain the effects that increasing the NaCl concentration had on osmotic pressure and why it
has this effect. ✔✔Increasing the NaCl will increase the osmotic pressure. because water needs
to diffuse to the higher concentration gradient until equilibrium is reached
Describe one way in which Osmosis is similar to simple diffusion and one way in which it is
different. ✔✔both are passive transports of high concentration gradient to low concentration
gradient. Osmosis differs because it is the diffusion of water from a high to a low concentration
gradient through a selective permeable membrane
the conditions were 9 mM albumin in the left beaker and 10 mM glucose in the right beaker
with the 200 MWCO membrane in place. Explain the results. ✔✔glucose diffuses from right
beaker to the left beaker until equilibrium is reached. albumin can't diffuse through the
membrane and osmotic pressure of 153mmHg results
which solute did not appear in the filtrate using any of the membranes? ✔✔activated charcoal
, why did increasing the pressure increased the filtration rate but not the concentration of
solutes? ✔✔because the pressure allows for more movement through the membrane but
equilibrium was not reached
describe the significance of using 9mM sodium chloride inside the cell and 6 mM potassium
chloride outside the cell, instead of other concentration ratio. ✔✔because the Na/K pump
allows for 3:2 ratio
Explain why there was no sodium transport even though ATP was present. ✔✔in order for
Na/K pump to function both ions need to be present even if ATP is present. since only Na was
present it would use a passive diffusion down the concentration gradient
Explain why the addition of glucose carriers had no effect on sodium or potassium transport.
✔✔because glucose concentration does not affect the Na/K concentration. it only has affect on
glucose itself
do you think glucose is being actively transported or transported by facilitated diffusion in this
experiment? explain you answer. ✔✔it is being transported by facilitated diffusion. since
glucose is a lipid insoluble and too large to pass through the membrane it requires a carrier but
not ATP
Which rat had the fastest basal metabolic rate (BMR)? ✔✔the normal rat
Why did the BMR's differ between the normal rat and the surgically altered rats? ✔✔The other
2 rats had either had the thyroid or pituitary gland surgically removed. This plays an important
part in hormone secretion to raise or lower BMR
If an animal had been thyroidectomized, what hormone(s) would be missing in its blood?
✔✔Thyroxine and Calcitonin
If an animal had been hypophysectomized, what effect(s) would you expect to see in the
hormone levels in its blood and in its BMR? ✔✔The metabolic rate would go down with no
pituitary gland to produce THS
What was the effect of thyroxine injections on the normal rat's BMR? ✔✔he metabolic rate
increased to 2000, which was higher than the baseline
What was the effect of thyroxine injections on the thyroidectomized rat's BMR?
How does the BMR in this case compare with the normal rat's BMR?
