Nursing Elites

1. Which statement accurately describes cytokinesis in animal cells?

• A. Which statement accurately describes cytokinesis in animal cells?
• B. A cell plate forms in the center of the dividing cell, eventually separating the cytoplasm into two daughter cells.
• C. A cell plate forms in the center of the dividing cell, eventually separating the cytoplasm into two daughter cells.
• D. The nucleus elongates and pulls apart, physically dividing the cytoplasm into two.

Correct answer: B

Rationale: Rationale: A) This statement is a duplicate of option C and does not accurately describe cytokinesis in animal cells. B) In animal cells, during cytokinesis, a cleavage furrow forms in the center of the dividing cell. This furrow deepens and eventually pinches the cytoplasm into two daughter cells. This process is distinct from plant cells, where a cell plate forms. C) This statement is a duplicate of option A and does not accurately describe cytokinesis in animal cells. D) This statement describes the process of nuclear division (mitosis) rather than cytokinesis, which is the division of the cytoplasm.

2. Which property of a substance describes how much matter is packed into a given space?

• A. Mass
• B. Volume
• C. Weight
• D. Density

Correct answer: D

Rationale: Density is the property of a substance that describes how much matter is packed into a given space. It is calculated by dividing the mass of the substance by its volume. Mass refers to the amount of matter in an object, volume is the amount of space an object occupies, and weight is the force of gravity acting on an object's mass. Density specifically relates to how tightly packed the particles of a substance are.

3. Which of the following is a strong acid?

• A. Acetic acid (CH₃COOH)
• B. Hydrochloric acid (HCl)
• C. Citric acid
• D. Carbonic acid (Hâ‚‚CO₃)

Correct answer: b

Rationale: Hydrochloric acid is a strong acid, meaning it completely ionizes in water to produce hydrogen ions. The other choices are weak acids.

4. The tiny contractile units within muscle cells are called:

• A. Myocytes
• B. Myofibrils
• C. Sarcomeres
• D. Tendons

Correct answer: C

Rationale: The correct answer is C: Sarcomeres. Sarcomeres are the basic contractile units within muscle cells. They are made up of overlapping filaments of actin and myosin proteins, which slide past each other during muscle contraction, resulting in muscle movement. Myocytes (A) are muscle cells, myofibrils (B) are cylindrical structures within muscle fibers composed of sarcomeres, and tendons (D) are tough bands of connective tissue that connect muscle to bone. Therefore, sarcomeres are specifically responsible for muscle contraction within muscle cells.

5. The doctor carefully examined the patient. Which word is the comparative form of the adjective "careful"?

• A. careful
• B. carelessly
• C. more careful
• D. most careful

Correct answer: C

Rationale: The comparative form of an adjective compares two things.

6. After exposure to a pathogen, the immune system develops memory. What type of immune cell is responsible for this immunological memory?

• A. B cells
• B. T cells (specifically memory T cells)
• C. Phagocytes
• D. Natural killer cells

Correct answer: B

Rationale: The correct answer is A: "B cells." B cells are responsible for generating immunological memory after exposure to a pathogen. When B cells encounter a pathogen, they differentiate into memory B cells, which can quickly recognize and respond to the pathogen upon subsequent exposure. These memory B cells are crucial for mounting a faster and more effective immune response, leading to a quicker clearance of the pathogen. T cells, phagocytes, and natural killer cells play important roles in the immune response, but specifically, memory B cells are responsible for immunological memory.

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