Nursing Elites

1. Which statement accurately describes the periodic trends in atomic radius?

• A. Increases down a group and decreases across a period
• B. Decreases down a group and increases across a period
• C. Remains constant throughout the table
• D. Fluctuates unpredictably based on individual elements

Correct answer: A

Rationale: The correct statement is that atomic radius increases down a group and decreases across a period. When moving down a group, additional electron shells increase the distance from the nucleus, leading to larger atomic radii. On the other hand, when moving across a period, the number of electron shells remains constant, but the increasing nuclear charge pulls electrons closer, resulting in smaller radii. Choice B is incorrect because atomic radius does not decrease down a group and increase across a period. Choice C is incorrect because atomic radius does not remain constant; it exhibits specific trends. Choice D is incorrect because atomic radius follows predictable trends based on the periodic table structure, rather than fluctuating unpredictably.

2. What is the energy required to break a chemical bond called?

• A. Kinetic energy
• B. Potential energy
• C. Activation energy
• D. Bond energy

Correct answer: C

Rationale: Activation energy is the energy required to break a chemical bond and initiate a chemical reaction. It is the minimum amount of energy needed to start a chemical reaction by breaking bonds in the reactant molecules. Kinetic energy (option A) is the energy of motion and is not directly related to breaking chemical bonds. Potential energy (option B) is stored energy that can be converted into other forms of energy but is not specifically about breaking chemical bonds. Bond energy (option D) refers to the energy required to break a particular chemical bond in a molecule and is not the general term for the energy needed to break any chemical bond. Activation energy is crucial in determining the rate of a chemical reaction as it affects the probability of reactant molecules colliding with sufficient energy to surpass the energy barrier and form products.

3. Which neurotransmitter is associated with mood regulation, sleep, and appetite?

• A. Acetylcholine
• B. Dopamine
• C. Serotonin
• D. GABA (Gamma-aminobutyric acid)

Correct answer: C

Rationale: The correct answer is C: Serotonin. Serotonin is a neurotransmitter that plays a crucial role in mood regulation, sleep, and appetite. It helps regulate emotions, mood, and behavior. Imbalances in serotonin levels have been associated with conditions such as depression, anxiety, and eating disorders. Choice A, Acetylcholine, is primarily involved in muscle control and memory functions. Choice B, Dopamine, is associated with reward, motivation, and motor control. Choice D, GABA (Gamma-aminobutyric acid), is an inhibitory neurotransmitter that helps reduce neuronal excitability and is not directly linked to mood regulation, sleep, or appetite.

4. What enzyme plays a key role in breaking down carbohydrates in the small intestine?

• A. Pepsin
• B. Lipase
• C. Amylase
• D. Trypsin

Correct answer: C

Rationale: Amylase is the enzyme responsible for breaking down carbohydrates in the small intestine. It specifically targets starches and sugars, breaking them down into smaller molecules like maltose and glucose that can be absorbed by the body. Pepsin is an enzyme that breaks down proteins in the stomach, not the small intestine. Lipase is responsible for breaking down fats, not carbohydrates. Trypsin is an enzyme that breaks down proteins in the small intestine, not carbohydrates.

5. Immunoglobulin G (IgG) is the most abundant antibody type, responsible for:

• A. Immediate allergic reactions
• B. Neutralizing toxins and viruses
• C. Activating other immune cells
• D. Protecting newborns from infections

Correct answer: B

Rationale: Immunoglobulin G (IgG) is indeed the most prevalent antibody type in the blood and tissue fluids. Its primary functions include neutralizing toxins and viruses, promoting phagocytosis, and activating the complement system. IgG plays a crucial role in long-term immunity and provides passive immunity to newborns by crossing the placenta, safeguarding them from infections. Immediate allergic reactions are mainly mediated by IgE, not IgG. While IgM is known for activating other immune cells, IgG focuses on other key functions within the immune response, such as neutralizing pathogens and enhancing phagocytosis. Therefore, the correct answer is B, as IgG is primarily involved in neutralizing toxins and viruses, rather than the other options presented.

Similar Questions