Nursing Elites

1. What is the main factor limiting population growth in K-strategists?

• A. Predation
• B. Availability of resources
• C. Competition
• D. Disease

Correct answer: B

Rationale: K-strategists are species with a low reproductive rate that invest more resources in raising fewer offspring. These species typically live in stable environments with limited resources. The main factor limiting population growth in K-strategists is the availability of resources such as food, shelter, and space. When resources are scarce, K-strategists may struggle to find enough to support their population size, leading to reduced reproductive success and population growth. While predation, competition, and disease can also impact population growth, the primary limiting factor for K-strategists is the availability of resources.

2. Which type of orbital can hold a maximum of 10 electrons?

• A. s orbital
• B. p orbital
• C. d orbital
• D. f orbital

Correct answer: D

Rationale: The correct answer is the f orbital. Each f orbital can hold up to 2 electrons. Since there are 5 f orbitals, the total maximum number of electrons that can be accommodated in f orbitals is 10 (2 electrons per orbital x 5 orbitals = 10 electrons). Therefore, the f orbital can hold a maximum of 10 electrons. Choice A, s orbital, is incorrect because it can hold a maximum of 2 electrons. Choice B, p orbital, is incorrect because it can hold a maximum of 6 electrons (3 orbitals x 2 electrons per orbital = 6 electrons). Choice C, d orbital, is incorrect as it can hold a maximum of 10 electrons (5 orbitals x 2 electrons per orbital = 10 electrons), but the question asks for the type of orbital that can hold a maximum of 10 electrons, not the total number of electrons in d orbitals.

3. What is the functional group present in aldehydes?

• A. Hydroxyl
• B. Carbonyl
• C. Ester
• D. Amine

Correct answer: B

Rationale: The correct answer is B: Carbonyl. Aldehydes contain the functional group -CHO, which is a carbonyl group where a carbon atom is double-bonded to an oxygen atom and single-bonded to a hydrogen atom. This distinguishes aldehydes from other functional groups. Choice A, Hydroxyl (-OH), is not characteristic of aldehydes as it is found in alcohols. Choice C, Ester (-COOR), and choice D, Amine (-NH2), represent different functional groups not typically found in aldehydes. Therefore, the correct functional group present in aldehydes is the carbonyl group.

4. What is the primary function of the atrioventricular (AV) node within the heart?

• A. Generate the electrical impulse for contraction (pacemaker function)
• B. Transmit the electrical impulse from the atria to the ventricles, regulating the timing of contraction.
• C. Increase blood pressure within the ventricles during systole.
• D. Separate oxygenated and deoxygenated blood flow in the heart.

Correct answer: B

Rationale: The correct answer is B: Transmit the electrical impulse from the atria to the ventricles, regulating the timing of contraction. The primary function of the atrioventricular (AV) node is to coordinate the transmission of electrical signals between the atria and the ventricles. It ensures proper timing between atrial and ventricular contractions, allowing for efficient blood pumping through the heart. Choice A is incorrect because the AV node does not generate the initial electrical impulse; that role is typically attributed to the sinoatrial (SA) node. Choice C is incorrect as the AV node does not directly influence blood pressure within the ventricles. Choice D is also incorrect as the separation of oxygenated and deoxygenated blood is primarily achieved by the anatomical structure of the heart (e.g., atria and ventricles) and not the AV node.

5. What is the role of transfer RNA (tRNA) in protein synthesis?

• A. Transcribes DNA into mRNA
• B. Decodes the genetic code on mRNA
• C. Carries specific amino acids to the ribosomes
• D. Modifies the structure of proteins

Correct answer: C

Rationale: A) Transcribes DNA into mRNA: This is the function of RNA polymerase, not transfer RNA (tRNA). tRNA is involved in protein synthesis, not transcription. B) Decodes the genetic code on mRNA: This is the function of tRNA during translation. tRNA molecules carry specific amino acids and recognize the codons on mRNA, ensuring the correct amino acid is added to the growing polypeptide chain. C) Carries specific amino acids to the ribosomes: This is the primary role of tRNA in protein synthesis. Each tRNA molecule is specific for a particular amino acid and carries it to the ribosome, where it is added to the growing protein chain. D) Modifies the structure of proteins: This is not a function of tRNA. Protein modification can occur after translation is complete and involves other cellular processes and molecules.

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