Name: act 1

Exercise 9: Renal System Physiology: Activity 1: The Effect of Arteriole Radius on Glomerular Filtration Lab Report

Pre-lab Quiz ResultsYou scored 100% by answering 5 out of 5 questions correctly.

1. There are approximately __________ nephrons in a healthy human kidney.You correctly answered: c. 1 × 106

2. Which of the following lists the anatomical structures in the correct order as they are encountered by the blood andfiltered fluid during the process of filtration?You correctly answered: d. afferent arteriole, glomerular capillary, Bowman's capsule

3. Bowman's capsule is connected to the beginning of theYou correctly answered: b. proximal convoluted tubule.

4. The functional unit of the kidney is theYou correctly answered: c. nephron.

5. During the process of renal reabsorption, fluid and solutes move from theYou correctly answered: b. renal tubule into the peritubular capillaries.

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Experiment ResultsPredict Question:Predict Question 1: What will happen to the glomerular capillary pressure and filtration rate if you decrease the radius of theafferent arteriole?Your answer : d. Pressure will increase and filtration rate will decrease.

Predict Question 2: What will happen to the glomerular capillary pressure and filtration rate if you increase the radius of theafferent arteriole?Your answer : d. Pressure will increase and filtration rate will decrease.

Predict Question 3: What will happen to the glomerular capillary pressure and filtration rate if you decrease the radius of theefferent arteriole?Your answer : d. Pressure will increase and filtration rate will decrease.

Stop & Think Questions:Caffeine consumption leads to increased urine formation. From the results in this experiment thus far, you might proposethatYou correctly answered: d. caffeine dilates the afferent arteriole.

When you are in the desert and dehydrating, which of the following arteriole combinations would benefit you the most?Your answer : d. afferent and efferent dilationCorrect answer: c. afferent constriction and efferent dilation

Experiment Data:

Afferent Radius(mm)

Efferent Radius(mm)

Beaker Press.(mm Hg)

Glomerular Press.(mm Hg)

Glom. Filt. Rate(ml/min)

Urine Volume(ml)

0.10 0.30 70 44.44 0.00 0.00

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Post-lab Quiz ResultsYou scored 50% by answering 2 out of 4 questions correctly.

1. If you increase the afferent arteriole radius and keep all other variables constant, the glomerular filtration rate wouldYou correctly answered: a. increase.

2. If you decrease the efferent arteriole radius and keep all other variables constant, the volume of urine flowing into theurinary bladder wouldYou correctly answered: a. increase.

3. If you increase the efferent arteriole radius and keep all other variables constant, the glomerular filtration rate wouldYour answer: a. increase.Correct answer: b. decrease.

4. If you decrease the afferent arteriole radius and keep all other variables constant, the volume of urine flowing into theurinary bladder would __________.Your answer: a. increase.Correct answer: b. decrease.

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Review Sheet Results1. What are two primary functions of the kidney?You did not answer this question.

2. What are the components of the renal corpuscle?You did not answer this question.

3. Starting with the renal corpuscle, list the components of the renal tubule as they are encountered by filtrate.You did not answer this question.

4. Describe the effect of decreasing the afferent arteriole radius on glomerular capillary pressure and filtration rate. Howwell did the results compare with your prediction?You did not answer this question.

5. Describe the effect of increasing the afferent arteriole radius on glomerular capillary pressure and filtration rate. Howwell did the results compare with your prediction?You did not answer this question.

6. Describe the effect of decreasing the efferent arteriole radius on glomerular capillary pressure and filtration rate. Howwell did the results compare with your prediction?You did not answer this question.

7. Describe the effect of increasing the efferent radius on glomerular capillary pressure and filtration rate.You did not answer this question.