Question

Select the correct statements.

1. Atrial Natriuretic Factor can cause constriction of blood vessels.
2. Renin converts angiotensinogen in blood to angiotensin I
3. Angiotensin II activates the adrenal cortex to release aldosterone.
4. Aldosterone causes release of Na" and water through distal convoluted tubule.

• A. ii, iv
• B. ii, iii
• C. i, iv
• D. ii only

Answer 1

Answer:

B. ii, iii

• Angiotensin is part of an elaborate group of linked hormones, enzymes, proteins and reactions called the renin-angiotensin-aldosterone system that helps regulate blood pressure.

• To start the system or cycle, when blood pressure falls, your kidneys release the enzyme renin into your bloodstream.

• Renin splits angiotensinogen, a protein made in your liver and releases the pieces.

• One piece is the hormone angiotensin I.

• Angiotensin I, which is inactive (doesn’t cause any effects), flows through your bloodstream and is split by angiotensin-converting enzyme (ACE) in your lungs and kidneys.

• One of those pieces is angiotensin II, an active hormone.

• Angiotensin II causes the muscular walls of small arteries (arterioles) to constrict (narrow), increasing blood pressure.

• Angiotensin II also triggers your adrenal glands to release aldosterone and your pituitary gland to release antidiuretic hormone (ADH, or vasopressin).

• Together, aldosterone and ADH cause your kidneys to retain sodium.