Lab Packet #8 Questions

What are two primary functions of the kidney?

The kidneys filter the body’s blood & it regulates blood pressure, blood volume, and plasma osmolarity

What are the components of the renal corpuscle?

Glomerulus & Bowman’s capsule

Starting at the renal corpuscle, list the components of the renal tubule as they are encountered by filtrate

Proximal convoluted tubule —> Loop of Henle —> Distal convoluted tubule —> Collecting duct

Describe the effect of decreasing the afferent arteriole radius on glomerular capillary pressure and filtration rate.

decreased glomerular capillary blood pressure and filtration rate

Describe the effect of increasing the afferent arteriole radius on glomerular capillary pressure and filtration rate

Increased glomerular capillary blood pressure and filtration rate

Describe the effect of decreasing the efferent arteriole radius in glomerular capillary pressure and filtration rate

Increased glomerular capillary blood pressure and filtration rate

Describe the effect of increasing the efferent radius on glomerular capillary pressure and filtration rate

Decreased glomerular capillary blood pressure and filtration rate

As blood pressure increased, what happened to the glomerular capillary pressure and the glomerular filtration rate?

As blood pressure increased, there will be increased glomerular capillary blood pressure and filtration rate

Compare the urine volume in your baseline date with the urine volume as you increased the blood pressure. How did the urine volume change?

When blood pressure increased, urine volume increased

How could the change in urine volume with the increase in blood pressure be viewed as being beneficial to the body?

When more urine is excreted, more water is being lost by the body which helps lower blood pressure

What happens to the concentration of glucose in the urinary bladder as the number of glucose carriers increases?

The glucose concentration in the bladder (and urine) decreased

What types of transport are utilized during glucose reabsorption and where do they occur?

Active transport and facilitated diffusion allow for the reabsorption of glucose at the proximal convoluted tubule

What do you think would happen to urine volume if you did not ADH to the collecting duct?

All of the glucose is reabsorbed by the body due to the presence of glucose carriers

Is most of the tubule filtrate reabsorbed into the body or excreted in urine? Explain?

The person is not able to store glucose in their tissues, so it remains in the urine

How did the addition of aldosterone affect urine volume (compared with baseline)? Can the reabsorption of solutes influence water reabsorption in the nephron?

It decreased urine volume. Water is reabsorbed (following the salts)

How did the addition of ADH affect urine volume (compared with baseline)? Why did the addition of ADH also affect the concentration of potassium in the urine (compared with baseline)

Adding ADH decreased urine volume. The reabsorption of Na+ causes water to follow

What is the principal determinant for the release of aldosterone from the adrenal cortex?

A decrease in systemic arterial blood pressure triggers aldosterone release

How did the addition of both aldosterone and ADH affect urine volume?

Both decreased urine volume

What is the principal determinant for the release of ADH from the posterior pituitary gland? Does ADH favor the formation of dilute or concentrated urine? Explain why?

A change in the osmolarity of body fluids and blood volume/ pressure trigger the release of ADH from the pituitary

Which hormone (aldosterone or ADH) has the greater effect on urine volume? why?

ADH has a greater effect since it directly acts on water reabsorption

If ADH is not available, can the urine concentration still vary?

Yes, aldosterone would be able to assist

Consider the situation: You want to reabsorb sodium ions, but you do not want to increase the volume of blood by reabsorbing a large amount of water from the filtrate. Assuming the aldosterone and ADH are both present, how would you adjust the hormones to accomplish the task?

you would secrete more aldosterone than ADH