Homeostasis is best described as:

Correct Answer: C

Rationale: Homeostasis maintains internal stability using nerves and hormones despite external changes.

Correct Answer: D

Rationale: Alcohol inhibits ADH, reducing water reabsorption and increasing urine output, leading to dehydration.

Correct Answer: A

Rationale: Saliva does not aid in protein digestion; it primarily helps in moistening food, contains amylase for carbohydrate digestion, and facilitates chemical digestion.

Correct Answer: A

Rationale: The duodenum is the first part of the small intestine where most chemical digestion takes place.

Correct Answer: A

Rationale: Lipids, or triglycerides, consist of three fatty acids attached to a glycerol molecule and provide energy storage.