Question 4 (0.75 points) Low blood pressure or blood volume, such as that caused by dehydration or blood loss, creates a cascade of events involving the following molecules (in order): renin - ADH - aldosterone - cortisol renin - angiotensinogen - angiotensin - aldosterone oxytocin - adrenaline - testosterone - ADH Aldosterone - angiotensinogen - renin ADH Saved

The correct cascade is **renin - angiotensinogen - angiotensin - aldosterone**.<br /><br />Here's why:<br /><br />* **Renin:** Released by the kidneys in response to low blood pressure or low blood volume.<br />* **Angiotensinogen:** A protein produced by the liver, renin converts it to angiotensin I.<br />* **Angiotensin I:** Converted to angiotensin II by an enzyme primarily found in the lungs.<br />* **Angiotensin II:** A powerful vasoconstrictor (narrows blood vessels, increasing blood pressure). It also stimulates the release of aldosterone.<br />* **Aldosterone:** A hormone released by the adrenal glands. It causes the kidneys to retain sodium and water, which increases blood volume and further raises blood pressure.<br /><br />The other options are incorrect because they include hormones not directly involved in this specific blood pressure regulation pathway or list them in the wrong order. Cortisol, while a stress hormone that can impact blood pressure, isn't a direct part of this renin-angiotensin-aldosterone system (RAAS). Oxytocin, adrenaline, and testosterone are also not key players in this specific response to low blood pressure/volume.<br />