The __________ are pointed teeth that are adapted for tearing and shredding.

Correct Answer: D

Rationale: The correct answer is D: cuspids. Cuspids, also known as canines, are pointed teeth that are specifically adapted for tearing and shredding food. They have long, sharp points that help in grasping and cutting food. Incisors (A) are flat-front teeth used for cutting and biting. Bicuspids (B) are premolars with two cusps used for grinding food. Molars (C) are large, flat teeth at the back of the mouth used for grinding and chewing. Therefore, D is the correct answer as cuspids are the pointed teeth adapted for tearing and shredding.

Correct Answer: D

Rationale: Step 1: The cephalic phase occurs before food enters the stomach, triggered by the sight, smell, or thought of food. Step 2: The vagus nerve sends signals to the stomach to prepare for food digestion during this phase. Step 3: Increased flow of action potentials along the vagus nerve stimulates gastric glands to secrete gastric juice. Step 4: Therefore, choice D is correct as it accurately describes the physiological response during the cephalic phase. Summary: Choices A and B are incorrect as they do not align with the physiological processes during the cephalic phase. Choice C is incorrect because distention of the stomach triggers the gastric phase, not the cephalic phase.

Correct Answer: C

Rationale: The correct answer is C: stomach. The stomach has 3 layers of smooth muscle in its muscularis externa, which help in mixing and churning food for digestion. The small intestine (A) has 2 layers of smooth muscle, the esophagus (B) has skeletal and smooth muscle, and the large intestine (D) has outer longitudinal and inner circular layers of smooth muscle, not 3 distinct layers like the stomach.

Correct Answer: C

Rationale: The correct answer is C because most ingested food molecules are large and need to be broken down into smaller molecules for absorption. Digestion involves the breakdown of complex nutrients into simpler forms that can be absorbed by the body. Choice A is incorrect because digestive enzymes can work on a variety of substrates, not necessarily requiring a variety. Choice B is incorrect as digestion is not primarily aimed at balancing the diet but rather extracting nutrients. Choice D is incorrect as digestion primarily occurs in the stomach and small intestine, not specifically to prevent disorders of the intestine.

Correct Answer: C

Rationale: The correct answer is C: an anticholinergic medication. Anticholinergic medications inhibit the action of acetylcholine, a neurotransmitter responsible for stimulating intestinal motility. By blocking acetylcholine, anticholinergics can effectively immobilize the intestines during surgery. Choice A (a cholinergic medication) would have the opposite effect by stimulating intestinal motility. Choice B (an antiadrenergic medication) is not directly related to immobilizing the intestines. Choice D is incorrect as only option C is the most effective at achieving intestinal immobilization.