Nursing Elites

1. Which of the following is NOT a primary producer in an ecosystem?

• A. Grass
• B. Deer
• C. Algae
• D. Mushroom

Correct answer: B

Rationale: Rationale: - A) Grass: Grass is a primary producer because it can photosynthesize and convert sunlight into energy, making it the base of the food chain. - B) Deer: Deer are consumers that feed on primary producers like grass, so they are not primary producers themselves. - C) Algae: Algae are primary producers that can photosynthesize and produce energy from sunlight. - D) Mushroom: Mushrooms are decomposers that break down organic matter, so they are not primary producers.

2. Deuterium, a stable isotope of hydrogen, has a nucleus containing:

• A. A single proton
• B. A proton and a neutron
• C. Two protons and an electron
• D. Two neutrons

Correct answer: B

Rationale: The correct answer is B: 'A proton and a neutron.' Deuterium is an isotope of hydrogen with an atomic number of 1, meaning it has 1 proton in its nucleus. However, deuterium also has a neutron in its nucleus, making it different from regular hydrogen which only has a proton in its nucleus. Therefore, deuterium has a nucleus containing both a proton and a neutron, making option B the correct choice.

3. The main function of the nephrons is to:

• A. Store urine
• B. Filter blood and remove waste products
• C. Produce hormones
• D. Control blood pressure

Correct answer: B

Rationale: The correct answer is B: 'Filter blood and remove waste products.' Nephrons are the functional units of the kidneys responsible for filtering blood to remove waste products, excess ions, and water, while reabsorbing essential substances like glucose and amino acids. This process forms urine, which is stored in the bladder before being excreted. Options A, C, and D are incorrect because nephrons do not store urine, produce hormones, or directly control blood pressure; although the kidneys do play a role in long-term blood pressure regulation through mechanisms like the renin-angiotensin-aldosterone system.

4. A ball is thrown upwards. At the peak of its trajectory, which of the following forces is acting on the ball?

• A. Gravity only
• B. Gravity and air resistance only
• C. Neither gravity nor air resistance
• D. All of the above

Correct answer: C

Rationale: At the peak of its trajectory, the ball has momentarily stopped moving upwards and has not yet started to fall back down. Therefore, there is no longer a net force acting on the ball at that instant. Gravity is acting downwards, but since the ball is not moving, the force of gravity is balanced by an equal and opposite force, resulting in a net force of zero. Similarly, air resistance only affects the ball when it is in motion, so at the peak where the ball momentarily stops, there is no air resistance force. Therefore, at the peak of its trajectory, neither gravity nor air resistance is acting on the ball, making option C the correct answer.

5. Nuclear fission is a process characterized by:

• A. A heavy nucleus capturing a neutron and releasing energy
• B. The fusion of two nuclei to form a heavier element
• C. A lighter element emitting an alpha particle through radioactive decay
• D. An electron being absorbed by the nucleus with the release of a gamma ray

Correct answer: A

Rationale: Nuclear fission is a process characterized by a heavy nucleus capturing a neutron and splitting into smaller nuclei, releasing a significant amount of energy in the form of heat and radiation. This differs from nuclear fusion, which involves the merging of two lighter nuclei to form a heavier element. The emission of an alpha particle by a lighter element is a form of radioactive decay, not fission. Absorption of an electron by the nucleus with the release of a gamma ray is not representative of fission reactions. Therefore, option A correctly describes the process of nuclear fission.

6. What is the scientific term for the involuntary rhythmic contraction and relaxation of the heart muscle?

• A. Peristalsis
• B. Myogenesis
• C. Myocardial contractility
• D. Systole and diastole

Correct answer: D

Rationale: The correct answer is D: Systole and diastole. Systole refers to the phase of the heartbeat when the heart muscle contracts and pumps blood out, while diastole is the phase when the heart muscle relaxes and fills with blood. This rhythmic contraction and relaxation of the heart muscle is crucial for maintaining blood circulation throughout the body. Peristalsis (option A) is the involuntary constriction and relaxation of the muscles of the gastrointestinal tract that pushes contents forward. Myogenesis (option B) is the formation of muscle tissue. Myocardial contractility (option C) refers to the ability of the heart muscle to contract. Therefore, the most appropriate term for the described process is systole and diastole.

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