Nursing Elites

1. What is the building block of DNA?

• A. Amino acid
• B. Nucleotide
• C. Nucleotide
• D. Fatty acid

Correct answer: B

Rationale: Rationale: - Amino acids are the building blocks of proteins, not DNA. - Nucleotide is the correct building block of DNA. A nucleotide consists of a sugar (deoxyribose in DNA), a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine). - The option "C) Nucleotide" is a duplicate of the correct answer "B) Nucleotide." - Fatty acids are not the building blocks of DNA; they are a type of lipid molecule.

2. The tiny air sacs in the lungs where gas exchange takes place are called:

• A. Bronchi
• B. Trachea
• C. Alveoli
• D. Pleura

Correct answer: A

Rationale: The correct answer is C: 'Alveoli.' Alveoli are the tiny air sacs in the lungs where gas exchange takes place. Oxygen from the air is diffused into the blood, and carbon dioxide from the blood is diffused into the air in the alveoli. Bronchi (option A) are the large air passages that lead from the trachea into the lungs. Trachea (option B) is the windpipe that connects the larynx to the bronchi. Pleura (option D) is a thin membrane that surrounds the lungs and lines the chest cavity. Understanding these structures is essential for comprehending respiratory function and gas exchange in the human body.

3. In the context of the cardiac cycle, the P wave on an electrocardiogram (ECG) represents:

• A. Atrial depolarization
• B. Ventricular depolarization
• C. Atrial repolarization
• D. Ventricular repolarization

Correct answer: A

Rationale: The correct answer is A: "Atrial depolarization." The P wave on an ECG represents the depolarization of the atria, specifically the spread of electrical activity through the atria causing them to contract and push blood into the ventricles. This is the first wave observed on the ECG and signifies the beginning of the cardiac cycle. Ventricular depolarization is represented by the QRS complex, atrial repolarization is typically not visible on a standard ECG due to its timing with the QRS complex, and ventricular repolarization is represented by the T wave. Therefore, option A is the most appropriate choice in this context.

4. You design an experiment to test the effectiveness of a new fertilizer. Which of the following factors would be considered a dependent variable?

• A. The type of fertilizer used
• B. The size and age of the plants
• C. The amount of plant growth observed
• D. The cost of the fertilizer per unit

Correct answer: C

Rationale: The dependent variable is the factor that is being measured or observed in an experiment. In this case, the amount of plant growth observed is the variable that is being influenced by the independent variable, which is the type of fertilizer used. The size and age of the plants (option B) could potentially be controlled variables, while the type of fertilizer used (option A) is the independent variable being tested. The cost of the fertilizer per unit (option D) is not directly related to the plant growth being measured in this experiment.

5. Which division of the nervous system is responsible for involuntary functions such as heart rate, digestion, and respiratory rate?

• A. Somatic nervous system
• B. Autonomic nervous system
• C. Peripheral nervous system
• D. Central nervous system

Correct answer: b

Rationale: The correct answer is B: Autonomic nervous system. The autonomic nervous system is responsible for regulating involuntary functions in the body, such as heart rate, digestion, respiratory rate, and other automatic processes. The somatic nervous system (A) controls voluntary muscle movements, the peripheral nervous system (C) consists of nerves outside the brain and spinal cord, and the central nervous system (D) includes the brain and spinal cord. Understanding the functions and divisions of the nervous system is crucial for grasping how different bodily processes are controlled and regulated.

6. Dense irregular connective tissue, found in tendons and ligaments, provides:

• A. Flexibility
• B. Lubrication
• C. Insulation
• D. Tensile strength

Correct answer: D

Rationale: The correct answer is D: 'Tensile strength.' Dense irregular connective tissue is composed of tightly packed collagen fibers arranged in a random pattern, providing resistance to tension forces. This structural arrangement is ideal for tendons and ligaments, as they need to withstand pulling and stretching forces. 'Flexibility' (A) is more characteristic of elastic fibers, 'Lubrication' (B) is provided by synovial fluid in joints, and 'Insulation' (C) is typically associated with adipose tissue. Therefore, tensile strength is the primary function of dense irregular connective tissue in tendons and ligaments.

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