what happens during expiration

ATI TEAS 7

ATI TEAS Science Practice Test

1. What happens during expiration?

A. The diaphragm contracts and the thoracic cavity expands.
B. The diaphragm relaxes and the thoracic cavity contracts.
C. The thoracic cavity expands, increasing pressure.
D. The diaphragm relaxes and moves upward.

Correct answer: B

Rationale: The correct answer is B. During expiration, the diaphragm relaxes, causing the thoracic cavity to contract. As the thoracic cavity decreases in size, the pressure inside the lungs increases, leading to air flowing out of the lungs. This process helps to expel carbon dioxide-rich air from the body. Choices A, C, and D are incorrect. In choice A, the diaphragm contracting and the thoracic cavity expanding describes inspiration, not expiration. Choice C is incorrect because during expiration, the thoracic cavity actually decreases in size. Choice D is incorrect as the diaphragm moving upward is not a typical movement associated with expiration.

2. How does meiosis differ from mitosis?

A. Meiosis is used for repairing the body. Mitosis is used for cell reproduction.
B. Meiosis is used for sexual reproduction. Mitosis is used for asexual reproduction.
C. Meiosis occurs in various organisms. Mitosis occurs in various organisms.
D. Meiosis produces cells that are genetically different. Mitosis produces cells that are genetically identical.

Correct answer: D

Rationale: Meiosis is the process of cell division that results in the formation of sex cells (gametes) with only half the number of chromosomes as the parent cell, leading to genetically different cells. In contrast, mitosis is a cell division process that produces two daughter cells that are genetically identical to each other and the parent cell, maintaining the same chromosome number. Therefore, the correct answer is D, as meiosis and mitosis differ in their genetic outcomes - meiosis results in genetic diversity, while mitosis maintains genetic identity. Choices A, B, and C are incorrect because they do not accurately distinguish between meiosis and mitosis. Meiosis is not used for repairing the body or asexual reproduction, and the occurrence of both processes in various organisms does not highlight their primary differences in genetic outcomes.

3. What type of muscle is found in the walls of the heart?

A. Smooth muscle
B. Cardiac muscle
C. Skeletal muscle
D. Voluntary muscle

Correct answer: B

Rationale: The correct answer is B: Cardiac muscle. Cardiac muscle is the specialized muscle found in the walls of the heart. It contracts involuntarily to pump blood throughout the body, ensuring circulation. Smooth muscle is typically found in organs like the intestines and blood vessels, aiding in their functions. Skeletal muscle is attached to bones and plays a vital role in movement and posture. Voluntary muscle is a general term for skeletal muscles that are under conscious control, unlike cardiac muscle which contracts involuntarily to maintain the heart's continuous pumping action.

4. Which of the following terms means toward the front of the body?

A. Superior
B. Anterior
C. Inferior
D. Posterior

Correct answer: B

Rationale: The correct answer is B: Anterior. The term 'anterior' specifically refers to the front of the body. In anatomical terms, anterior is the opposite of posterior, which means toward the back of the body. Superior and inferior, choices A and C, respectively, refer to top and bottom directions, not front and back. Therefore, 'Anterior' is the most appropriate term for describing a position toward the front of the body.

5. What function do hydrophobic proteins often provide in the body?

A. Digestive enzymes
B. Provide structure
C. Carry oxygen molecules
D. Store energy

Correct answer: B

Rationale: Hydrophobic proteins are known for their ability to repel water and are often involved in providing structural support in cells and tissues. They help maintain the structural integrity and shape of cell membranes, organelles, and other cellular components. Choice A, digestive enzymes, typically consist of hydrophilic proteins that interact with water and substrates to facilitate digestion. Choice C, carrying oxygen molecules, is a function commonly associated with specific proteins like hemoglobin. Choice D, storing energy, is usually performed by proteins like enzymes involved in energy storage and release, such as glycogen phosphorylase.