Nursing Elites

1. In a covalent bond, the shared electrons:

• A. Are completely transferred to one atom.
• B. Spend more time closer to the more electronegative atom.
• C. Remain equidistant between the two atoms.
• D. Do not influence the bond strength.

Correct answer: B

Rationale: In a covalent bond, the shared electrons spend more time closer to the more electronegative atom. Electronegativity is the ability of an atom to attract electrons in a chemical bond. The more electronegative atom exerts a stronger pull on the shared electrons, causing them to be closer to that atom. Choice A is incorrect because in a covalent bond, electrons are shared, not completely transferred. Choice C is incorrect as the shared electrons are not equidistant but are closer to one atom due to electronegativity differences. Choice D is incorrect because shared electrons play a significant role in determining the bond strength by the strength of the bond formed through electron sharing.

2. How do organisms maintain homeostasis?

• A. By increasing their body temperature, blood pH, and fluid balance.
• B. By undergoing biochemical processes and absorbing energy to increase entropy.
• C. By undergoing biochemical processes to maintain the order of their external environment.
• D. By using free energy and matter via biochemical processes to work against entropy.

Correct answer: D

Rationale: Organisms maintain homeostasis by utilizing free energy and matter through biochemical processes to counteract entropy, which helps in preserving internal stability. This process involves maintaining a balance within the organism's internal environment despite external changes, ensuring proper functioning and survival. Choice A is incorrect because increasing body temperature, blood pH, and fluid balance alone do not define the comprehensive process of maintaining homeostasis. Choice B is incorrect as absorbing energy to increase entropy goes against the concept of maintaining internal stability. Choice C is incorrect as maintaining the order of the external environment does not directly contribute to the organism's internal stability and balance.

3. A satellite orbits the Earth at a constant speed. Which force is responsible for its circular motion?

• A. Gravitational force from the Earth
• B. Thrust from the satellite's engine
• C. Friction between the satellite and the atmosphere
• D. Normal force from the Earth's surface

Correct answer: A

Rationale: The gravitational force from the Earth is responsible for keeping the satellite in its circular orbit. This force provides the necessary centripetal force required to maintain the circular motion of the satellite. The gravitational force acts as the centripetal force, pulling the satellite towards the center of the Earth, thereby keeping it in its circular path. Choices B, C, and D do not provide the necessary force to keep the satellite in its circular path. Thrust from the satellite's engine would change the speed or direction of the satellite, not maintain its circular path. Friction between the satellite and the atmosphere would act as a resistive force, slowing down the satellite rather than maintaining its orbit. The normal force from the Earth's surface is perpendicular to the surface and does not contribute to the circular motion of the satellite. Therefore, the correct answer is A, as the gravitational force acts as the centripetal force to keep the satellite in its circular path around the Earth.

4. What type of epithelium lines the inner surface of blood vessels?

• A. Simple squamous epithelium
• B. Simple columnar epithelium
• C. Stratified squamous epithelium
• D. Stratified columnar epithelium

Correct answer: A

Rationale: The correct answer is simple squamous epithelium (Choice A). The inner surface of blood vessels is lined by a single layer of flattened cells, known as simple squamous epithelium. This epithelium type is thin and allows for efficient diffusion and filtration, which is essential for the exchange of gases and nutrients across blood vessel walls. Simple columnar epithelium (Choice B) is typically found in the lining of the gastrointestinal tract and is responsible for absorption and secretion. Stratified squamous epithelium (Choice C) is commonly found in the skin, providing protection against mechanical stress. Stratified columnar epithelium (Choice D) is not a characteristic epithelium type found in the lining of blood vessels, as it is more commonly present in specific regions of the body like parts of the male urethra and the conjunctiva of the eye.

5. In the human skeleton, which of the following lists some of the vertebrae in descending order?

• A. Atlas, axis, thoracic, lumbar, sacral, coccyx.
• B. Axis, sacral, coccyx, atlas, lumbar, thoracic.
• C. Thoracic, sacral, lumbar, axis, coccyx, atlas.
• D. Coccyx, lumbar, axis, sacral, thoracic, atlas.

Correct answer: A

Rationale: The correct order of some of the vertebrae in the human skeleton in descending order is Atlas, Axis, Thoracic, Lumbar, Sacral, Coccyx. This sequence follows the typical arrangement from the top of the spine down towards the pelvis. Choice B is incorrect as it does not follow the descending order of vertebrae. Choice C is incorrect as it starts with Thoracic which is not the first vertebra in the descending order. Choice D is incorrect as it starts with Coccyx which is the last vertebra in the descending order.

Similar Questions