which of the following immune cells are part of the innate immune response

ATI TEAS 7

TEAS Practice Test Science

1. Which of the following immune cells are part of the innate immune response?

A. B-cells
B. Cytotoxic T-cells
C. Natural Killer cells
D. Antigen-Presenting Cells

Correct answer: C

Rationale: Natural Killer cells are a crucial component of the innate immune response. They play a significant role in defending against infected or cancerous cells through their ability to identify and kill abnormal cells. B-cells (Choice A) and Cytotoxic T-cells (Choice B) are part of the adaptive immune response, which involves a more specific and targeted response to pathogens. Antigen-Presenting Cells (Choice D) are also part of the adaptive immune response, where they present antigens to activate other immune cells.

2. Which statement confirms that the cell membrane is selectively permeable?

A. Receptors are found on a cell's surface.
B. Cells communicate with each other using cell signals.
C. Environmental changes can cause a cell to expand or shrink.
D. Sodium ions must travel through ion channels to enter the cell.

Correct answer: D

Rationale: The correct answer is D because selective permeability is demonstrated by the fact that specific ions, such as sodium, require ion channels to cross the cell membrane. This process allows the cell to control what substances can enter or exit, highlighting the selective nature of the cell membrane. Choices A, B, and C do not directly relate to the concept of selective permeability of the cell membrane. Receptors on a cell's surface (Choice A) are involved in cell signaling rather than selective permeability. Cell communication through signals (Choice B) and environmental changes affecting cell size (Choice C) are not directly related to the selective permeability of the cell membrane, which specifically refers to the regulation of substances passing through the membrane.

3. Which process is characterized by nuclear fission?

A. A heavy nucleus capturing a neutron and releasing energy
B. The fusion of two nuclei to form a heavier element
C. A lighter element emitting an alpha particle through radioactive decay
D. An electron being absorbed by the nucleus with the release of a gamma ray

Correct answer: A

Rationale: Nuclear fission is the process where a heavy nucleus, like uranium-235, captures a neutron, leading to its division into two lighter nuclei. This process releases a substantial amount of energy in the form of heat and gamma rays. It is utilized in nuclear power plants and atomic bombs due to its capacity to produce significant energy. Choices B, C, and D describe different nuclear processes: fusion of two nuclei to form a heavier element, emission of alpha particles from a lighter element through radioactive decay, and absorption of an electron by the nucleus with the release of a gamma ray, respectively. These processes are distinct from nuclear fission and do not involve the splitting of heavy nuclei into lighter ones.

4. What is the muscular tube that connects the mouth to the stomach?

A. Pharynx
B. Esophagus
C. Trachea
D. Larynx

Correct answer: B

Rationale: The correct answer is B: Esophagus. The esophagus is indeed the muscular tube that connects the mouth to the stomach. Food is transported down the esophagus via peristalsis, a series of muscle contractions. The pharynx is the area behind the mouth and nasal cavity, the trachea connects the larynx to the bronchi in the lungs, and the larynx is the voice box located in the throat. Therefore, choices A, C, and D are incorrect in the context of the question.

5. Which part of the brain controls breathing and heart rate?

A. Cerebrum
B. Medulla oblongata
C. Thalamus
D. Cerebellum

Correct answer: B

Rationale: The medulla oblongata is the correct answer because it is responsible for controlling involuntary functions such as breathing and heart rate. The cerebrum (Choice A) is primarily associated with higher brain functions like thinking and voluntary movements, not with regulating basic bodily functions like breathing and heart rate. The thalamus (Choice C) serves as a relay station for sensory information but is not directly involved in controlling breathing and heart rate. The cerebellum (Choice D) plays a role in coordination and balance, not in regulating respiratory and cardiac functions.