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 : b. Both pressure 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 : b. Both pressure 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?You correctly answered: 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)

0.50 0.45 90 55.08 124.99 200.440.45 0.45 90 51.54 81.06 179.880.40 0.45 90 48.52 43.66 143.910.35 0.45 90 46.16 14.35 76.330.55 0.45 90 58.94 172.86 212.870.60 0.45 90 62.88 221.69 220.740.50 0.45 90 55.08 124.99 200.440.50 0.40 90 56.10 137.69 227.490.50 0.35 90 56.84 146.82 247.960.50 0.30 90 57.34 152.96 262.23

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Post-lab Quiz ResultsYou scored 100% by answering 4 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 wouldYou correctly answered: 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 __________.You correctly answered: b. decrease.

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Review Sheet Results1. What are two primary functions of the kidney?Your answer:1.- regular la osmolaridad del plasma.2.- regular el equilibrio de electrolitos en el organismo.

2. What are the components of the renal corpuscle?Your answer:-glomérulo-capsula de bowman

3. Starting with the renal corpuscle, list the components of the renal tubule as they are encountered by filtrate.Your answer:-corpusculo renal.-tubulo contorneado proximal.-asa de henle.-tubulo contorneado distal.-conducto colector.

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?Your answer:Al disminuir el radio de la arteriola aferente se da la disminucion de la presion del capilar glomerular y filtracion glomerular;las predicciones fueron correctas.

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?Your answer:Al aumentar el radio de la arteriola aferente, la presion del capilar glomerular aumento junto con la taza de filtracionglomerular, la prediccion fue herrada.

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?Your answer:Al dismiuir el radio de la arteriola eferente, la presion del capilar glomerular aumento junto con la taza de filtracion.

7. Describe the effect of increasing the efferent radius on glomerular capillary pressure and filtration rate.Your answer:Al aumentar el radio de la arteriola eferente, ambas: la presión del capilar glomerular y la tasa de filtración disminuyen