Nursing Elites

1. Which element is a critical component of DNA and RNA, essential for storing and transmitting genetic information?

• A. Oxygen
• B. Carbon
• C. Nitrogen
• D. Hydrogen

Correct answer: B

Rationale: Carbon is the correct answer as it is a critical element in DNA and RNA, forming the backbone of these molecules. Its ability to form diverse bonds allows for efficient storage and transmission of genetic information. Oxygen, nitrogen, and hydrogen are also present in DNA and RNA but do not serve as the primary backbone element for these molecules. Oxygen is involved in the structure but not as the backbone element. Nitrogen is present in the bases of nucleotides, and hydrogen bonds help stabilize the structure.

2. What is the molar mass of Ca(NO3)2?

• A. 74.1 g/mol
• B. 132.1 g/mol
• C. 164.1 g/mol
• D. 78.1 g/mol

Correct answer: B

Rationale: To calculate the molar mass of Ca(NO3)2, we add up the individual atomic masses of its elements: Ca (40.08) + 2N (2 * 14.01) + 6O (6 * 16.00) = 40.08 + 28.02 + 96.00 = 164.1 g/mol. Therefore, the correct answer is 164.1 g/mol (Choice C). Choice A (74.1 g/mol) is incorrect as it does not account for the correct sum of atomic masses. Choice B (132.1 g/mol) is the correct molar mass calculation for Ca(NO3)2. Choice D (78.1 g/mol) is incorrect and does not reflect the accurate molar mass of the compound.

3. The adaptive immune system develops a targeted response to specific pathogens. What type of immune cell is responsible for producing antibodies?

• A. Natural killer cells
• B. Phagocytes
• C. Helper T cells
• D. B cells

Correct answer: D

Rationale: B cells are responsible for producing antibodies as part of the adaptive immune response. When activated by a specific antigen, B cells differentiate into plasma cells that secrete antibodies to target and neutralize pathogens. Natural killer cells are primarily involved in killing infected or cancerous cells, phagocytes engulf pathogens, and helper T cells assist in activating other immune cells. Therefore, the correct answer is B cells because they play a crucial role in antibody production, a key component of the adaptive immune response.

4. What type of genetic variation is caused by changes in the DNA sequence?

• A. Epigenetic variation
• B. Phenotypic variation
• C. Genotypic variation
• D. Behavioral variation

Correct answer: C

Rationale: A) Epigenetic variation refers to changes in gene expression that do not involve alterations in the DNA sequence itself. These changes can be influenced by environmental factors. B) Phenotypic variation refers to differences in observable traits or characteristics of an organism, which can be influenced by both genetic and environmental factors. C) Genotypic variation is caused by changes in the DNA sequence, such as mutations or genetic recombination. These changes directly impact the genetic information carried by an organism. D) Behavioral variation refers to differences in behavior among individuals of the same species, which can be influenced by genetic, environmental, and experiential factors.

5. Which of the following areas has the least amount of sweat glands?

• A. Back
• B. Palms
• C. Axilla
• D. Forehead

Correct answer: B

Rationale: The correct answer is B - Palms. The palms have the least amount of sweat glands compared to the other options listed. The back, axilla (armpits), and forehead are all areas with a higher concentration of sweat glands in the body. The palms have fewer sweat glands to minimize water loss and maintain a better grip for activities requiring precise and controlled movement. The back, axilla, and forehead have more sweat glands to assist in thermoregulation and cooling of the body, while the palms have fewer sweat glands for functional reasons related to grip and dexterity.

Similar Questions