Question

1. What is the major force/pressure that causes filtration?

2. What is the major force/pressure that causes reabsorption?

3. What would happen to the filtration rate if glomerular capillaries were damaged to an extent to be leaky to plasma proteins?

Identifying how renal arterioles affect GFR

Complete the following table that describes how changes in the diameters of these resistance vessels affect glomerular hydrostatic pressure and GFR (assuming no change in renal arterial pressure) with no change, increase, or decrease.

Afferent Arteriole	Efferent Arteriole	Glomerular Hydrostatic Pressure and Filtration Rate
No change	No change	Normal
Constricts	No change
No change	Constricts
Dilates	No change
Dilates	Constricts

How renal arterioles respond to changes in blood pressure

Changes in mean arterial pressure (MAP) can lead to wide changes in systemic pressure, including the renal arteries. Use your understanding of the renal mechanisms identified in part and your understanding of cardiovascular physiology and blood pressure to answer the following questions.

1. In the human body, if MAP is between 80 and 160mmHg, would GFR be expected to change as MAP changes? Explain your answer, including in your answer the afferent arteriolar response, what stimulates it to do so (2 stimuli), and the purpose of this response.

1. GFR:

2. afferent arteriole response:

3. two stimuli of response:

4. purpose of response:

2. What would happen to GFR if MAP rises above 160mmHg? Explain your answer, including in your answer what each arteriole does, what stimulates their responses, and the purpose of their responses.

1. GFR:

2. afferent arteriole response:

3. efferent arteriole response:

4. stimulus for responses:

5. purpose of responses:

3. What would happen to GFR if MAP falls below 80mmHg? Explain your answer, including in your answer what each arteriole does, what stimulates their responses, and the purpose of their responses.

1. GFR:

2. afferent arteriole response:

3. efferent arteriole response:

4. stimulus for responses:

5. purpose of responses:

Answer 1