Nursing Elites

1. What are chromosomes made of?

• A. DNA and RNA
• B. DNA and proteins
• C. Proteins and carbohydrates
• D. DNA only

Correct answer: B

Rationale: Rationale: Chromosomes are structures found in the nucleus of cells that contain genetic material. They are made up of DNA (deoxyribonucleic acid), which carries the genetic information, and proteins that help in the organization and packaging of the DNA. While RNA is involved in various cellular processes, it is not a major component of chromosomes. Carbohydrates are not a significant component of chromosomes. Therefore, the most accurate answer is B) DNA and proteins.

2. What is the CRISPR-Cas9 system used for in gene editing?

• A. To amplify specific DNA sequences.
• B. To cut DNA at specific locations.
• C. To deliver genes into cells.
• D. To sequence entire genomes.

Correct answer: B

Rationale: Rationale: The CRISPR-Cas9 system is a powerful tool used in gene editing to precisely target and cut DNA at specific locations within the genome. This system consists of a guide RNA that directs the Cas9 enzyme to the desired DNA sequence, where it creates a double-strand break. This break can then be repaired by the cell's natural DNA repair mechanisms, allowing for the introduction of specific genetic modifications. Options A, C, and D do not accurately describe the primary function of the CRISPR-Cas9 system in gene editing.

3. Which of the following is NOT a characteristic of a chemical reaction?

• A. Formation of new substances
• B. Release or absorption of energy
• C. Change in color
• D. Change in temperature

Correct answer: C

Rationale: While color change can be an indicator of a chemical reaction, it's not always present, and some reactions occur without a visible color change.

4. The dark, round structures observed within some bacterial cells are most likely:

• A. Ribosomes
• B. Flagella
• C. Endospores
• D. Capsules

Correct answer: C

Rationale: Rationale: - Ribosomes are not dark, round structures within bacterial cells. Ribosomes are small, non-membranous organelles responsible for protein synthesis in all cells. - Flagella are not dark, round structures within bacterial cells. Flagella are long, whip-like appendages that some bacteria use for movement. - Capsules are not dark, round structures within bacterial cells. Capsules are outer layers of polysaccharides that some bacteria produce for protection and adherence. - Endospores are dark, round structures observed within some bacterial cells. Endospores are dormant, highly resistant structures formed by certain bacteria in response to harsh environmental conditions.

5. Which state of matter has both definite volume and definite shape?

• A. Solid
• B. Liquid
• C. Gas
• D. Plasma

Correct answer: a

Rationale: Solids have both definite volume and definite shape. The particles in solids are closely packed, maintaining their positions, resulting in a fixed shape and volume.

6. What type of joint allows for the most movement?

• A. Ball-and-socket joint (shoulder)
• B. Hinge joint (elbow)
• C. Fibrocartilaginous joint (wrists)
• D. Suture joint (skull)

Correct answer: A

Rationale: Rationale: A ball-and-socket joint allows for the most movement among the options provided. This type of joint is characterized by a rounded end of one bone fitting into a cup-like socket of another bone, allowing for a wide range of motion in multiple directions. The shoulder joint is a prime example of a ball-and-socket joint, enabling movements such as flexion, extension, abduction, adduction, and rotation. In contrast, a hinge joint (option B) like the elbow primarily allows for movement in one plane (flexion and extension). Fibrocartilaginous joints (option C) like the wrists have limited movement due to the presence of cartilage between the bones. Suture joints (option D) in the skull are immovable joints that provide structural support but do not allow for significant movement.

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