Starvation and Waste Products in the Body

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What is the primary function of the renal cortex in the kidney?

To provide structural support and blood supply to the kidney
To filter blood and form urine (correct)
To collect urine from the renal pyramids
To produce urea from ammonia

Which of the following is a product of nucleic acid catabolism in the body?

Creatinine
Uric acid (correct)
Urea
Ammonia

What is the role of the liver in the formation of urea?

The liver converts ammonia to urea (correct)
The liver filters blood and removes urea from the body
The liver stores urea for later use in the body
The liver synthesizes urea from amino acids

What is the primary function of the renal medulla in the kidney?

To concentrate urine by reabsorbing water (A) Signup and view all the answers

What is the primary function of the nephron, the basic structural and functional unit of the kidney?

To filter blood and form urine (C) Signup and view all the answers

What percentage of the body's cardiac output is received by the kidneys?

21% (C) Signup and view all the answers

What is the main function of the distal convoluted tubule (DCT) in urine formation?

Reabsorption of sodium and potassium (A) Signup and view all the answers

How does the ascending limb of the nephron loop create a salinity gradient?

By pumping solutes out into the extracellular fluid (ECF) (A) Signup and view all the answers

What is the primary role of the collecting duct in the urinary system?

Concentration of urine and conservation of water (B) Signup and view all the answers

What role does tubular reabsorption play in urine formation?

Adds useful solutes to the blood (A) Signup and view all the answers

Which part of the nephron forms a juxtaglomerular apparatus by contacting the renal corpuscle?

Distal convoluted tubule (DCT) (C) Signup and view all the answers

In urine formation, what is the function of tubular secretion?

Adds wastes to the blood (D) Signup and view all the answers

What is the net effect of Aldosterone on the body?

Retention of Na+, Cl−, and water (A) Signup and view all the answers

What stimulates the secretion of Aldosterone from the adrenal cortex?

Drop in blood pressure (D) Signup and view all the answers

What is the main action of Antidiuretic Hormone (ADH) on the kidney?

Increases permeability of collecting duct to water (A) Signup and view all the answers

Which condition is characterized by a proportionate loss of water and sodium with normal osmolarity?

Volume Depletion (Hypovolemia) (C) Signup and view all the answers

What can lead to Syndrome of Inappropriate Antidiuretic Hormone (SIADH)?

Tumors that secrete excessive ADH (B) Signup and view all the answers

What is a common cause of Dehydration (negative water balance)?

Lack of drinking water (D) Signup and view all the answers

Which statement is true regarding osmotic pressure?

It is the tendency of water to move from a region of high solute concentration to a region of low solute concentration across a semipermeable membrane. (A) Signup and view all the answers

If two solutions are isosmotic, what can be inferred about their osmotic pressures?

Both solutions have the same osmotic pressure. (B) Signup and view all the answers

If a hyposmotic solution is placed on one side of a semipermeable membrane and a hyperosmotic solution is placed on the other side, which way will the net movement of water occur?

From the hyposmotic solution to the hyperosmotic solution. (B) Signup and view all the answers

What percentage of the total body water (TBW) is typically found in the intracellular fluid (ICF) compartment?

65% (A) Signup and view all the answers

Which of the following systems is NOT mentioned as contributing to the maintenance of homeostatic balance in the body?

Reproductive system (A) Signup and view all the answers

Which of the following types of homeostatic balance is NOT mentioned in the text?

Temperature balance (B) Signup and view all the answers

Which mechanism is primarily responsible for the kidney's ability to maintain a relatively stable glomerular filtration rate (GFR) despite changes in systemic blood pressure?

Myogenic mechanism (A) Signup and view all the answers

In the tubuloglomerular feedback mechanism, what happens when the glomerular filtration rate (GFR) is high?

The macula densa stimulates the juxtaglomerular cells to contract, constricting the afferent arteriole and reducing GFR. (C) Signup and view all the answers

What is the role of the sympathetic nervous system in regulating glomerular filtration?

Sympathetic nerve fibers innervate the afferent arterioles and cause them to constrict, reducing GFR and urine output. (B) Signup and view all the answers

What is the primary function of the mesangial cells in the juxtaglomerular apparatus?

Contracting or relaxing to modify the surface area of the glomerular capillaries and regulate GFR. (C) Signup and view all the answers

In the myogenic mechanism of autoregulation, what happens when arterial blood pressure increases?

The afferent arteriole constricts, reducing the glomerular hydrostatic pressure and GFR. (A) Signup and view all the answers

What is the primary role of the macula densa in the tubuloglomerular feedback mechanism?

Sensing changes in the filtrate composition and regulating the afferent arteriole accordingly. (C) Signup and view all the answers