the esophagus is part of the

HESI A2

Anatomy HESI A2

1. Which system does the esophagus belong to?

A. Endocrine system
B. Digestive system
C. Respiratory system
D. Nervous system

Correct answer: B

Rationale: The esophagus is part of the digestive system. It is a muscular tube that connects the mouth to the stomach, allowing the passage of food and liquids from the mouth to the stomach for digestion. The esophagus plays a crucial role in the process of swallowing and digestion, which are essential functions of the digestive system. Choices A, C, and D are incorrect because the esophagus is not associated with the endocrine, respiratory, or nervous systems.

2. What is the normal pH of human arterial blood?

A. 6.8
B. 7.4
C. 7.9
D. 8.2

Correct answer: B

Rationale: The normal pH of human arterial blood is approximately 7.4. This slightly alkaline pH is crucial for the proper functioning of enzymes and biochemical processes in the body. Any significant deviation from this pH level can result in serious health issues such as acidosis or alkalosis. Choice A (6.8) is incorrect as it is lower than the normal pH of arterial blood, indicating acidity. Choice C (7.9) and Choice D (8.2) are incorrect as they are higher than the normal pH of arterial blood, indicating alkalinity.

3. Which organelle is responsible for generating energy within a cell?

A. Nucleus
B. Ribosome
C. Mitochondria
D. Golgi apparatus

Correct answer: C

Rationale: Mitochondria are commonly referred to as the powerhouses of the cell as they are primarily responsible for generating energy through cellular respiration. This process involves converting nutrients into adenosine triphosphate (ATP), which is the main energy currency of the cell. The nucleus is responsible for storing the cell's genetic material, the ribosome is involved in protein synthesis, and the Golgi apparatus is responsible for packaging and distributing molecules produced by the cell; therefore, they are not directly involved in energy generation.

4. Which gland is located superior to the kidney?

A. Pituitary
B. Adrenal
C. Hypothalamus
D. Pancreas

Correct answer: B

Rationale: The adrenal gland is located superior to the kidney. Each kidney is surrounded by an adrenal gland, also known as the suprarenal gland, situated on top of the kidneys. The pituitary gland (A) is located in the brain, while the hypothalamus (C) is also in the brain, above the pituitary gland. The pancreas (D) is located in the abdomen, near the stomach and small intestine, not superior to the kidney.

5. Where does digestion begin in the digestive system?

A. Stomach
B. Mouth
C. Small intestine
D. Esophagus

Correct answer: B

Rationale: Digestion begins in the mouth. Mechanical digestion through chewing and chemical digestion through saliva initiate the breakdown of food. Enzymes in saliva start breaking down carbohydrates, marking the beginning of the digestive process. The stomach primarily functions in further breaking down food and mixing it with gastric juices. The small intestine is where most of the digestion and absorption of nutrients occur. The esophagus is a muscular tube that helps move food from the mouth to the stomach, but digestion does not begin there.