Nursing Elites

1. Select the option that best shows complementary base pairing in DNA:

• A. A and G
• B. A and C
• C. A and A
• D. A and T

Correct answer: D

Rationale: The correct answer is D. A purine (A) must pair with a pyrimidine (T) in DNA. This eliminates options A and C as they do not follow the rule of complementary base pairing. Adenine (A) always pairs with thymine (T) due to their specific shape and bonding properties in DNA structure. Choice B is incorrect because adenine does not pair with cytosine in DNA.

2. Which of these molecules contains glucose?

• A. Proteins
• B. Lipids
• C. Nucleic acids
• D. Carbohydrates

Correct answer: D

Rationale: Glucose is a type of simple sugar and is classified as a carbohydrate. It is commonly found in various carbohydrate-containing foods such as fruits, vegetables, grains, and sugary snacks. Therefore, the molecule containing glucose would be a carbohydrate, making choice D the correct answer. Proteins (choice A) are made up of amino acids, lipids (choice B) are fats, and nucleic acids (choice C) are DNA and RNA, none of which contain glucose.

3. What kind of symbiosis exists between a pneumonia bacterium and a human?

• A. Mutualism
• B. Parasitism
• C. Commensalism
• D. Competition

Correct answer: B

Rationale: In the case of a pneumonia bacterium and a human, the relationship is best described as parasitism. The bacterium benefits by causing harm to the human host, while the human is negatively affected by the presence of the bacterium, leading to illness or infection. This is a classic example of a parasitic relationship where one organism benefits at the expense of the other. Mutualism (Choice A) is a type of symbiotic relationship where both organisms benefit from each other. Commensalism (Choice C) is a symbiotic relationship where one organism benefits, and the other is neither helped nor harmed. Competition (Choice D) refers to a relationship where both organisms are negatively affected by each other as they compete for resources.

4. What is the first step in the conversion of glucose to pyruvate?

• A. Glycolysis
• B. Krebs cycle
• C. Electron transport chain
• D. Aerobic respiration

Correct answer: A

Rationale: The correct answer is Glycolysis. Glycolysis is the initial step in the conversion of glucose to pyruvate. During glycolysis, glucose is broken down into pyruvate through a series of enzymatic reactions. Choice B, the Krebs cycle, occurs after glycolysis in aerobic cellular respiration. Choice C, the Electron transport chain, is the final step in aerobic respiration where the majority of ATP is produced. Choice D, Aerobic respiration, is a broader term that encompasses glycolysis, the Krebs cycle, and the electron transport chain, but it is not the specific first step in the conversion of glucose to pyruvate.

5. Enzymes can _ reactions.

• A. Catalyze
• B. Inhibit
• C. Stop
• D. None of the above

Correct answer: A

Rationale: Enzymes function as catalysts that promote and accelerate chemical reactions in biological systems. They do this by lowering the activation energy required for the reactions to occur, thereby speeding up the process without being consumed in the reaction. Enzymes facilitate reactions rather than inhibiting or stopping them. Therefore, the correct answer is 'Catalyze.' 'Inhibit' and 'Stop' are incorrect because enzymes do not hinder or halt reactions but rather enhance them.

Similar Questions