Nursing Elites

1. What substance is required to drive the sliding filament process during muscle contraction?

• A. ATP
• B. Hormone
• C. Potassium
• D. Water

Correct answer: A

Rationale: The substance required to drive the sliding filament process during muscle contraction is ATP (adenosine triphosphate). ATP provides the energy needed for muscle contraction by enabling the myosin heads to bind to actin and generate force. This energy release drives the sliding of the filaments, causing muscle fibers to contract. Hormones, potassium, and water do not directly drive the sliding filament process in muscle contraction. Hormones are signaling molecules that regulate various physiological processes but do not directly provide energy for muscle contraction. Potassium is an electrolyte important for nerve and muscle function but is not the primary driver of the sliding filament process. Water is essential for overall hydration and bodily functions but does not directly participate in the muscle contraction process.

2. What is the shape of the DNA molecule?

• A. Linear
• B. Circular
• C. Double helix
• D. Straight chain

Correct answer: C

Rationale: The correct answer is C: Double helix. The shape of the DNA molecule is a double helix, a structure first described by James Watson and Francis Crick in 1953. This shape consists of two strands twisted around each other in a spiral. The double helix structure allows DNA to be compactly stored within the cell nucleus and provides stability to the molecule. Options (A) Linear, (B) Circular, and (D) Straight chain are incorrect as they do not accurately represent the shape of the DNA molecule. DNA is not linear but rather forms a twisted double helix; it is not circular like a ring but has a spiral structure, and it is not a straight chain but a twisted ladder-like structure.

3. What happens to the gravitational potential energy of an object as it falls freely?

• A. It decreases
• B. It increases
• C. It remains constant
• D. It becomes zero

Correct answer: A

Rationale: The correct answer is A: 'It decreases.' When an object falls freely, its height decreases, resulting in a decrease in gravitational potential energy. The potential energy is converted into kinetic energy as the object accelerates due to gravity. This conversion process continues until the object reaches the ground or its lowest point, where the gravitational potential energy is minimal or zero. Choice B is incorrect because gravitational potential energy decreases, not increases, during free fall. Choice C is incorrect as gravitational potential energy changes due to the change in height. Choice D is incorrect as the gravitational potential energy does not instantly become zero but decreases gradually as the object falls.

4. What is the name of a condition where the heart rate is 118 beats per minute (bpm)?

• A. Tachycardia
• B. Apnea
• C. Bradycardia
• D. Tachypnea

Correct answer: A

Rationale: The correct answer is A: Tachycardia. Tachycardia is a condition characterized by a heart rate that exceeds the normal resting rate, typically above 100 bpm. In this case, a heart rate of 118 bpm falls within the range of tachycardia. Apnea (choice B) refers to the temporary cessation of breathing, not related to heart rate. Bradycardia (choice C) is a condition of an abnormally slow heart rate, opposite of the given heart rate. Tachypnea (choice D) is an abnormally rapid breathing rate, not related to heart rate.

5. Which of the following statements regarding the pericardium is not correct?

• A. It allows for the heart to work in a relatively friction-free environment
• B. It is a single-walled layer around the heart
• C. It prevents overfilling of the heart with blood
• D. It protects and anchors the heart

Correct answer: B

Rationale: The correct statement about the pericardium is that it is double-walled, not single-walled. Choice A is correct because the pericardium does allow the heart to work in a relatively friction-free environment, reducing friction during heartbeats. Choice C is correct as the pericardium helps prevent the overfilling of the heart with blood. Choice D is also correct as the pericardium serves to protect and anchor the heart in place within the chest cavity.

Similar Questions