Nursing Elites

1. Which of the following is NOT a risk factor for developing atherosclerosis?

• A. High blood pressure
• B. High levels of LDL cholesterol
• C. Regular physical activity
• D. Smoking

Correct answer: C

Rationale: Regular physical activity is NOT a risk factor for developing atherosclerosis. In fact, engaging in regular physical activity can help reduce the risk of developing atherosclerosis by improving cardiovascular health, lowering blood pressure, and reducing LDL cholesterol levels. High blood pressure, high levels of LDL cholesterol, and smoking are all known risk factors for atherosclerosis. High blood pressure can damage blood vessels, making them more susceptible to plaque buildup. High levels of LDL cholesterol can lead to the accumulation of plaque in the arteries, narrowing the passageways and increasing the risk of atherosclerosis. Smoking is harmful to blood vessels, promoting inflammation and the formation of plaque. Therefore, regular physical activity is actually a protective factor against atherosclerosis rather than a risk factor.

2. Which of the following is responsible for generating the electrical impulses that regulate the heartbeat?

• A. Aorta
• B. Pulmonary veins
• C. Coronary arteries
• D. Sinoatrial (SA) node

Correct answer: D

Rationale: The correct answer is D: Sinoatrial (SA) node. The SA node, also known as the heart's natural pacemaker, is responsible for generating the electrical impulses that regulate the heartbeat. These impulses initiate each heartbeat by causing the atria to contract. The other options, Aorta, Pulmonary veins, and Coronary arteries, are important structures in the cardiovascular system but are not directly responsible for generating the electrical impulses that regulate the heartbeat.

3. 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: The correct answer is A: Parathyroid hormone (PTH). PTH is produced by the parathyroid glands and plays a crucial role in regulating calcium levels in the blood. When blood calcium levels are low, PTH is released to stimulate the release of calcium from bones, increase calcium absorption in the intestines, and reduce calcium loss in the kidneys. This process helps to maintain the necessary balance of calcium in the body. Calcitonin, on the other hand, works in opposition to PTH by decreasing blood calcium levels. Growth hormone primarily stimulates growth and development of tissues, while testosterone is a male sex hormone and does not directly impact calcium regulation.

4. What is the purpose of the spindle apparatus in cell division?

• A. To separate sister chromatids
• B. To move chromosomes to opposite poles of the cell
• C. To form a new nuclear envelope around each daughter cell
• D. To synthesize new DNA

Correct answer: B

Rationale: Rationale: The spindle apparatus is a structure composed of microtubules that plays a crucial role in cell division (mitosis and meiosis). Its main purpose is to ensure the proper separation and distribution of chromosomes to opposite poles of the cell during cell division. This process is essential for the formation of two genetically identical daughter cells in mitosis or four haploid daughter cells in meiosis. Option A is incorrect because the separation of sister chromatids specifically refers to the role of the kinetochore fibers within the spindle apparatus. Option C is incorrect because the formation of a new nuclear envelope occurs after the chromosomes have been properly segregated. Option D is incorrect because DNA synthesis does not occur within the spindle apparatus; it takes place during the S phase of the cell cycle.

5. The fatty sheath that insulates some nerve fibers and speeds up signal transmission is called the:

• A. Myelin sheath
• B. Dura mater
• C. Pia mater
• D. Arachnoid mater

Correct answer: A

Rationale: The correct answer is A: Myelin sheath. The myelin sheath is a fatty layer that surrounds and insulates certain nerve fibers. It acts as an electrical insulator, speeding up the transmission of nerve impulses along the axon. This insulation helps to prevent signal loss or interference, allowing for faster and more efficient communication between neurons. The other options, B: Dura mater, C: Pia mater, and D: Arachnoid mater, are all layers of the meninges that protect the brain and spinal cord, but they do not play a role in insulating nerve fibers for signal transmission like the myelin sheath does.

6. What is the name of the growth plates in children's bones where new bone tissue is formed?

• A. Epiphyses
• B. Diaphysis
• C. Periosteum
• D. Medullary cavity

Correct answer: A

Rationale: The correct answer is A: Epiphyses. Epiphyses are the growth plates located at the ends of children's long bones where new bone tissue is formed. These plates are responsible for longitudinal bone growth until they close during adolescence. The diaphysis (B) is the shaft or main portion of a long bone, while the periosteum (C) is the outer membrane covering the bone. The medullary cavity (D) is the central cavity of bone shafts where bone marrow is stored. Understanding the terminology for different parts of bones is essential for comprehending bone growth and development in children.

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