Nursing Elites

1. Which of the following bases is not present in RNA?

• A. Adenine
• B. Thymine
• C. Uracil
• D. Cytosine

Correct answer: B

Rationale: Thymine is not present in RNA. RNA uses uracil as one of its bases, which pairs with adenine. In RNA, adenine does not pair with thymine as in DNA. Cytosine and guanine are the other two bases found in both RNA and DNA.

2. What is the function of decomposition in the carbon cycle?

• A. To produce light energy
• B. To convert carbon to fuel
• C. To release carbon dioxide
• D. To store food for consumers

Correct answer: C

Rationale: The correct answer is C: 'To release carbon dioxide.' Decomposition in the carbon cycle involves breaking down dead organic matter into simpler substances. During this process, carbon is released in the form of carbon dioxide back into the atmosphere. This release of carbon dioxide is essential for recycling carbon and making it available for use by living organisms. Choices A, B, and D are incorrect because decomposition does not produce light energy, convert carbon to fuel, or store food for consumers; its primary role is to recycle carbon through the release of carbon dioxide.

3. Which organelle contains the genetic material of the cell?

• A. Golgi apparatus
• B. Ribosome
• C. Endoplasmic reticulum
• D. Nucleus

Correct answer: D

Rationale: The correct answer is 'D: Nucleus.' The nucleus is the organelle that contains the cell's genetic material, which is the DNA. The genetic material in the nucleus controls the cell's activities and plays a crucial role in inheritance. Choices A, B, and C are incorrect because the Golgi apparatus is involved in modifying, sorting, and packaging of proteins; ribosomes are involved in protein synthesis; and endoplasmic reticulum is involved in protein and lipid synthesis and transportation, but none of them contain the genetic material of the cell.

4. Which one of the following best describes the function of a cell membrane?

• A. It controls the substances entering and leaving the cell.
• B. It maintains the cell's shape.
• C. It controls the substances entering the cell.
• D. It supports the cell's structures.

Correct answer: A

Rationale: The correct answer is A. The function of a cell membrane is to control the substances entering and leaving the cell. The cell membrane is selectively permeable, allowing it to regulate the movement of ions and molecules in and out of the cell to maintain internal balance and proper function. Choice B is incorrect because while the cell membrane does provide some structural support, its primary function is not to maintain the cell's shape. Choice C is incorrect because the cell membrane controls both the substances entering and leaving the cell, not just those entering. Choice D is incorrect as the primary function of the cell membrane is not to support the cell's structures but to regulate the movement of substances.

5. In an example of a male with hemophilia and a female carrier, what ratio of the offspring are predicted neither to carry nor to manifest the disease?

• A. 0 females : 1 male
• B. 1 female : 1 male
• C. 1 female : 0 males
• D. 2 females : 1 male

Correct answer: D

Rationale: In this scenario, the male offspring will inherit the Y chromosome from the father and the X chromosome from the carrier mother. As a result, they will not have the hemophilia gene. The female offspring will inherit one X chromosome from the mother, which does not carry the hemophilia gene, and one X chromosome from the father, which does not exist due to the Y chromosome. Therefore, all female offspring will not carry or manifest hemophilia, resulting in a ratio of 2 females to 1 male. Choice A is incorrect because it does not account for the female offspring. Choices B and C are incorrect as they do not reflect the correct ratio based on the inheritance pattern of hemophilia.

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