Nursing Elites

1. Which type of isomerism arises due to differences in the arrangement of atoms around a double bond?

• A. Chain isomerism
• B. Functional group isomerism
• C. Cis-trans isomerism
• D. Stereoisomerism

Correct answer: C

Rationale: Cis-trans isomerism, also known as geometric isomerism, arises due to differences in the arrangement of atoms around a double bond. In cis isomers, similar groups are on the same side of the double bond, while in trans isomers, similar groups are on opposite sides of the double bond. This type of isomerism is a subset of stereoisomerism, which includes all isomers that have the same connectivity but differ in spatial arrangement. Chain isomerism involves differences in the carbon chain arrangement, functional group isomerism involves different functional groups, and stereoisomerism is a broader category that encompasses isomers with the same connectivity but different spatial arrangement.

2. Which muscles play a significant role in the process of forced exhalation by contracting to reduce the thoracic cavity volume?

• A. Diaphragm
• B. External intercostal muscles
• C. Internal intercostal muscles
• D. Abdominal muscles

Correct answer: D

Rationale: The abdominal muscles play a significant role in forced exhalation by contracting to reduce the thoracic cavity volume. When these muscles contract, the pressure within the thoracic cavity increases, assisting in the expulsion of air from the lungs. This action helps to compress the abdomen and push the diaphragm upwards, further decreasing the volume of the thoracic cavity and aiding in the exhalation process. The diaphragm (Choice A) is mainly involved in inhalation by contracting and moving downward to increase thoracic cavity volume. External intercostal muscles (Choice B) and internal intercostal muscles (Choice C) are primarily involved in the process of inhalation by expanding the thoracic cavity during normal breathing, rather than forced exhalation.

3. What is the 'lock-and-key' model?

• A. Protein folding
• B. Enzyme-substrate interaction
• C. Muscle contraction
• D. Blood clotting

Correct answer: B

Rationale: The 'lock-and-key' model describes the specificity of the interaction between enzymes and their substrates. In this model, the enzyme's active site acts like a lock that can only be opened by the specific substrate molecule, which serves as the key. This specific binding ensures that enzymes catalyze particular reactions and do not interact with other molecules indiscriminately. Protein folding (option A) is the process by which a protein attains its functional three-dimensional structure but is not directly related to the lock-and-key model. Muscle contraction (option C) and blood clotting (option D) are complex biological processes but are not directly associated with the lock-and-key model of enzyme-substrate interaction.

4. What happens when an atom loses an electron?

• A. It forms a molecule.
• B. It gains a positive charge and becomes an ion.
• C. It alters its elemental identity.
• D. No change occurs; it remains neutral.

Correct answer: B

Rationale: When an atom loses an electron, it gains a positive charge and becomes an ion. This occurs because the number of protons in the atom exceeds the number of electrons, leading to a positive charge. Therefore, the atom undergoes a transformation into an ion by losing an electron. Choice A is incorrect because losing an electron does not result in the formation of a molecule, as molecules are made up of bonded atoms. Choice C is incorrect because losing an electron does not change the fundamental identity of the atom; it only changes its charge. Choice D is incorrect because losing an electron causes the atom to become positively charged, altering its neutrality.

5. What are the key differences between cytokinesis in plant and animal cells?

• A. Animal cells utilize an actomyosin ring for cleavage furrow formation, while plant cells lack this mechanism.
• B. Plant cells rely on the assembly of a cell plate in the center of the dividing cell, ultimately separating the cytoplasm.
• C. Cytokinesis in both plant and animal cells is driven by the expansion of the endoplasmic reticulum.
• D. Both types of cells achieve cytokinesis through similar membrane pinching and constriction mechanisms.

Correct answer: B

Rationale: Rationale: A) Animal cells utilize an actomyosin ring for cleavage furrow formation, while plant cells lack this mechanism. - This statement is true. Animal cells use an actomyosin ring to form a cleavage furrow during cytokinesis, while plant cells do not have this mechanism. Instead, plant cells form a cell plate. B) Plant cells rely on the assembly of a cell plate in the center of the dividing cell, ultimately separating the cytoplasm. - This statement is correct. Plant cells form a cell plate in the middle of the dividing cell during cytokinesis. The cell plate eventually develops into a new cell wall that separates the two daughter cells. C) Cytokinesis in both plant and animal cells is driven by the expansion of the endoplasmic reticulum. - This

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