Nursing Elites

1. Which of the following describes a scalar quantity?

• A. Velocity
• B. Acceleration
• C. Force
• D. Speed

Correct answer: D

Rationale: A scalar quantity is a physical quantity that has magnitude only, without any direction. Speed is an example of a scalar quantity because it only describes how fast an object is moving without specifying the direction of motion. Velocity, acceleration, and force are vector quantities because they have both magnitude and direction. Therefore, the correct answer is 'Speed.' Choices A, B, and C are incorrect because velocity, acceleration, and force are all vector quantities that involve both magnitude and direction.

2. Which structure of the respiratory system bifurcates into the primary bronchi?

• A. Trachea
• B. Alveoli
• C. Bronchioles
• D. Larynx

Correct answer: A

Rationale: The trachea is the structure that bifurcates into the primary bronchi. The trachea is a tube that carries air to and from the lungs. It divides into the left and right primary bronchi at a specific point called the carina, which then further divide into secondary and tertiary bronchi, leading to the bronchioles. The alveoli are the tiny air sacs at the end of the bronchioles where gas exchange occurs, not the structure that bifurcates into the primary bronchi. Bronchioles are smaller airway branches that come after the bronchi but do not bifurcate into them. The larynx, also known as the voice box, is located above the trachea and is responsible for sound production, not the bifurcation into primary bronchi. Therefore, the correct answer is the trachea.

3. What type of vessel carries oxygen-rich blood from the heart to other tissues of the body?

• A. Veins
• B. Intestines
• C. Bronchioles
• D. Arteries

Correct answer: D

Rationale: The correct answer is D: Arteries. Arteries are blood vessels that carry oxygen-rich blood away from the heart to supply oxygen to the tissues and organs throughout the body. Veins, choice A, carry oxygen-poor blood back to the heart, not oxygen-rich blood. Intestines, choice B, are part of the digestive system and do not play a role in carrying blood. Bronchioles, choice C, are small air passages in the lungs responsible for carrying air, not blood.

4. A pediatrician notes that an infant's cartilage is disappearing and being replaced by bone. What process has the doctor observed?

• A. Mineralization
• B. Ossification
• C. Osteoporosis
• D. Calcification

Correct answer: B

Rationale: The doctor has observed the process of ossification. Ossification is the natural process where cartilage in the body is replaced by bone. This process takes place during fetal development, growth, and bone fracture healing. Ossification involves the formation of bone tissue by depositing minerals like calcium and phosphorus within the cartilage matrix, leading to the development of a bone structure. Choice A, mineralization, refers to the process of forming mineral deposits in tissues, but it does not involve the replacement of cartilage by bone. Choice C, osteoporosis, is a condition characterized by bone density loss and increased fragility, not the natural process of cartilage replacement by bone. Choice D, calcification, is the process of deposition of calcium salts in various tissues, but it does not specifically involve the replacement of cartilage by bone as in ossification.

5. Which hormone stimulates the release of calcium from bones and increases blood calcium levels?

• A. Parathyroid hormone (PTH)
• B. Calcitonin
• C. Growth hormone
• D. Testosterone

Correct answer: A

Rationale: Parathyroid hormone (PTH) is the correct answer. PTH stimulates the release of calcium from bones, leading to increased blood calcium levels. It acts on the bones to release calcium into the bloodstream, facilitates the kidneys' reabsorption of calcium, and triggers vitamin D activation to boost calcium absorption from the intestines. Choice B, Calcitonin, is incorrect as it works in opposition to PTH by decreasing blood calcium levels through inhibiting calcium release from bones. Choices C and D, Growth hormone and Testosterone, are not directly involved in calcium homeostasis and do not regulate blood calcium levels through bone calcium release mechanisms.

Similar Questions