Nursing Elites

1. Which valve prevents the return of blood into the right ventricle?

• A. Pulmonary semilunar valve
• B. Aortic semilunar valve
• C. Tricuspid valve
• D. Mitral valve

Correct answer: A

Rationale: The correct answer is A: Pulmonary semilunar valve. The pulmonary semilunar valve is located between the right ventricle and the pulmonary artery. It opens to allow blood to be pumped into the pulmonary artery but closes to prevent blood from returning back into the right ventricle. The aortic semilunar valve is located between the left ventricle and the aorta. The tricuspid valve is located between the right atrium and right ventricle, and the mitral valve is located between the left atrium and left ventricle. Therefore, the pulmonary semilunar valve is the specific valve responsible for preventing the backflow of blood into the right ventricle during the cardiac cycle.

2. Which mineral is crucial for bone strength and is stored in bones and teeth?

• A. Calcium
• B. Iron
• C. Magnesium
• D. Potassium

Correct answer: A

Rationale: Calcium is crucial for bone strength as it is a major mineral stored in bones and teeth. It plays a vital role in maintaining bone density and strength, making it essential for overall bone health. Calcium is essential for various physiological functions, including muscle contraction, nerve transmission, and blood clotting. Inadequate calcium intake can lead to conditions like osteoporosis, where bones become weak and brittle. Iron (Choice B) is important for transporting oxygen in the blood, but it is not stored in bones and does not play a significant role in bone strength. Magnesium (Choice C) is essential for bone health, but it is not primarily stored in bones and teeth. Potassium (Choice D) is crucial for various physiological functions, such as fluid balance and muscle function, but it is not a major mineral stored in bones and teeth for bone strength.

3. What is the process by which a cell divides to produce two daughter cells?

• A. Mitosis
• B. Meiosis
• C. Differentiation
• D. Transformation

Correct answer: A

Rationale: Mitosis is the correct answer because it is the process of cell division that results in the production of two daughter cells with identical genetic material to the parent cell. Meiosis, while also involving cell division, leads to the formation of gametes with half the number of chromosomes as the parent cell. Differentiation is the specialization of cells for specific functions, not the process of cell division. Transformation involves a cell incorporating foreign DNA into its genome, which is unrelated to the division of a cell into two daughter cells.

4. The tonsils and adenoids, located in the throat, are part of the:

• A. Lymphatic system
• B. Endocrine system
• C. Respiratory system
• D. Digestive system

Correct answer: A

Rationale: The tonsils and adenoids are part of the lymphatic system, not the respiratory, endocrine, or digestive systems. The lymphatic system plays a crucial role in the body's defense against infections and diseases by producing white blood cells and lymphatic fluid, which help in filtering harmful substances. The respiratory system is primarily responsible for breathing and gas exchange in the body, the endocrine system regulates hormones, and the digestive system is involved in the breakdown and absorption of nutrients from food. Therefore, the correct answer is the lymphatic system.

5. Which type of mutation involves a change in the number of chromosomes?

• A. Point mutation
• B. Frameshift mutation
• C. Missense mutation
• D. Aneuploidy

Correct answer: D

Rationale: A) Point mutation involves a change in a single nucleotide base pair within the DNA sequence. B) Frameshift mutation involves the insertion or deletion of nucleotides, causing a shift in the reading frame of the genetic code. C) Missense mutation involves a single nucleotide change that results in a codon that codes for a different amino acid. D) Aneuploidy involves a change in the number of chromosomes, where an individual may have an extra chromosome (trisomy) or a missing chromosome (monosomy). Aneuploidy can lead to genetic disorders such as Down syndrome (trisomy 21) or Turner syndrome (monosomy X). Changing the number of chromosomes is a characteristic feature of aneuploidy, making it the correct answer. Point mutation, frameshift mutation, and missense mutation do not involve a change in the number of chromosomes and are focused on alterations at the nucleotide level within the DNA sequence.

Similar Questions