Nursing Elites

1. What is the primary function of the strong nuclear force?

• A. Binding electrons in atomic orbitals
• B. Binding protons and neutrons within the nucleus
• C. Mediating the attractive force between opposite charges
• D. Mediating the repulsive force between like charges

Correct answer: B

Rationale: The strong nuclear force primarily functions to bind protons and neutrons within the nucleus. It is responsible for overcoming the electrostatic repulsion between positively charged protons, holding the nucleus together. Choices A, C, and D are incorrect because the strong nuclear force specifically acts on nucleons (protons and neutrons) within the nucleus, not on electrons in atomic orbitals or charges outside the nucleus.

2. Which level of protein structure is defined by the folds and coils of the protein's polypeptide backbone?

• A. Primary
• B. Secondary
• C. Tertiary
• D. Quaternary

Correct answer: B

Rationale: The correct answer is B: Secondary. The secondary structure of a protein is defined by the folding and coiling of the polypeptide backbone into structures like alpha helices and beta sheets. Secondary structure primarily involves interactions such as hydrogen bonding within the backbone. This level of protein structure is distinct from primary structure (A) which refers to the linear sequence of amino acids, tertiary structure (C) which involves the overall 3D arrangement of a single polypeptide chain, and quaternary structure (D) which pertains to the interaction between multiple polypeptide chains in a protein complex.

3. The patella, commonly known as the kneecap, is an example of a:

• A. Sesamoid bone
• B. Long bone
• C. Short bone
• D. Irregular bone

Correct answer: A

Rationale: The patella, also known as the kneecap, is an example of a sesamoid bone. Sesamoid bones develop within tendons, such as the patellar tendon in this case. The patella is embedded in the tendon of the quadriceps muscle, enhancing the mechanical advantage of the muscle and protecting the knee joint. Long bones, like the femur, are characterized by their elongated shape with growth plates at the ends. Short bones, such as those in the wrist and ankle, are cube-shaped bones. Irregular bones, like vertebrae, do not fit into the other bone shape categories due to their unique shapes and functions.

4. Memory B cells and memory T cells are crucial for immunological memory. How does immunological memory enhance the immune response upon re-exposure to a pathogen?

• A. It increases the production of the same ineffective antibodies.
• B. It allows for a quicker and more robust immune response.
• C. It suppresses the immune system to prevent overreaction.
• D. It triggers a completely different immune response.

Correct answer: B

Rationale: Immunological memory enhances the immune response upon re-exposure to a pathogen by allowing for a quicker and more robust immune response. Memory B cells and memory T cells are primed to recognize the pathogen quickly and mount a faster and more effective response, leading to a more efficient clearance of the pathogen. Choice A is incorrect because immunological memory does not increase the production of ineffective antibodies but rather promotes the production of specific antibodies that are effective against the pathogen. Choice C is incorrect as immunological memory does not suppress the immune system; instead, it enhances the response. Choice D is incorrect because immunological memory leads to a recall of the specific immune response mounted during the initial exposure, not a completely different response.

5. What are the key differences between cytokinesis in plant and animal cells?

• A. Animal cells utilize an actomyosin ring for cleavage furrow formation, while plant cells lack this mechanism.
• B. Plant cells rely on the assembly of a cell plate in the center of the dividing cell, ultimately separating the cytoplasm.
• C. Cytokinesis in both plant and animal cells is driven by the expansion of the endoplasmic reticulum.
• D. Both types of cells achieve cytokinesis through similar membrane pinching and constriction mechanisms.

Correct answer: B

Rationale: Rationale: A) Animal cells utilize an actomyosin ring for cleavage furrow formation, while plant cells lack this mechanism. - This statement is true. Animal cells use an actomyosin ring to form a cleavage furrow during cytokinesis, while plant cells do not have this mechanism. Instead, plant cells form a cell plate. B) Plant cells rely on the assembly of a cell plate in the center of the dividing cell, ultimately separating the cytoplasm. - This statement is correct. Plant cells form a cell plate in the middle of the dividing cell during cytokinesis. The cell plate eventually develops into a new cell wall that separates the two daughter cells. C) Cytokinesis in both plant and animal cells is driven by the expansion of the endoplasmic reticulum. - This

Similar Questions