Question

19 multiple choice 2 points
which of the following is a nephron associated blood vessel network that is housed in the renal corpuscle and contributes to the first step of urine formation?

• none of the above
• hepatic portal system
• glomerulus
• all of the above
• hypophyseal portal system

20 multiple choice 2 points
extrinsic control of the bronchiole radius through the autonomic nervous system includes bronchodilation which is regulated through the sympathetic nervous system by ____ and bronchoconstriction which is regulated through the parasympathetic nervous system by ____.

• histamine ; carbon dioxide
• epinephrine ; acetylcholine
• nitrogen ; dopamine
• serotonin ; gaba (gamma-aminobutyric acid)

21 multiple choice 2 points
which of the following is utilized for regulation of metabolic pathways?

• none of the above
• all of the above
• number of enzymes (degradation/synthesis)

Explanation:

Identify the nephron-associated blood vessel network in the renal corpuscle

The renal corpuscle consists of the glomerulus (a capillary network) and Bowman's capsule. The glomerulus is the site of the first step of urine formation (glomerular filtration).

Determine autonomic regulation of bronchiole radius

Sympathetic stimulation causes bronchodilation, mediated primarily by epinephrine (acting on \(\beta_2\)-adrenergic receptors). Parasympathetic stimulation causes bronchoconstriction, mediated by acetylcholine (acting on muscarinic receptors).

Analyze regulation of metabolic pathways

Metabolic pathways are regulated by multiple mechanisms, including controlling the number of enzymes (via synthesis/degradation), compartmentalization of enzymes/substrates, and allosteric regulation. Therefore, "all of the above" is the correct choice.

Answer:

Question 19

• none of the above
• hepatic portal system
• glomerulus (Correct answer)
• all of the above
• hypophyseal portal system

Question 20

• histamine ; carbon dioxide
• epinephrine ; acetylcholine (Correct answer)
• nitrogen ; dopamine
• serotonin ; GABA (gamma-aminobutyric acid)

Question 21

• none of the above
• all of the above (Correct answer)
• number of enzymes (degradation/synthesis)