Nursing Elites

1. What is the independent variable in the botanist's experiment?

• A. Temperature
• B. Root tissue
• C. Light exposure
• D. Root length

Correct answer: A

Rationale: In an experiment, the independent variable is the factor that is deliberately manipulated or changed by the researcher. The botanist is likely altering the temperature to observe its effect on the plants. Therefore, temperature is the independent variable in the botanist's experiment. Choice B, root tissue, is not the independent variable as it is not the factor being intentionally changed in the experiment. Choice C, light exposure, and choice D, root length, are also not the independent variables as they are not the factors being purposely manipulated by the researcher in this scenario.

2. What is the balanced chemical equation for the reaction between sulfuric acid (H2SO4) and potassium hydroxide (KOH)?

• A. H2SO4 + KOH → K2SO4 + H2O
• B. 2H2SO4 + 2KOH → 2K2SO4 + 2H2O
• C. H2SO4 + 2KOH → K2SO4 + 2H2O
• D. H2SO4 + 2KOH → K2SO4 + H2O

Correct answer: C

Rationale: When sulfuric acid (H2SO4) reacts with potassium hydroxide (KOH), it forms potassium sulfate (K2SO4) and water (H2O). To balance the equation, 2 KOH molecules are required to react with 1 H2SO4 molecule, resulting in 1 K2SO4 molecule and 2 H2O molecules. Therefore, the balanced chemical equation is H2SO4 + 2KOH → K2SO4 + 2H2O, which corresponds to option C. Choice A is incorrect because it does not account for the correct stoichiometry between the reactants and products. Choice B incorrectly doubles all the molecules in the reaction, leading to an unbalanced equation. Choice D incorrectly balances the equation with 1 KOH molecule instead of the required 2 KOH molecules, making it unbalanced. Thus, option C is the correct balanced chemical equation for the reaction between sulfuric acid and potassium hydroxide.

3. What is the term for the time it takes for a wave to complete one full cycle?

• A. Frequency
• B. Amplitude
• C. Period
• D. Wavelength

Correct answer: C

Rationale: The period of a wave is the time it takes for one complete cycle to occur. It is the duration between two successive points in the wave that are in the same phase. Frequency, on the other hand, refers to the number of cycles of a wave that occur in a given time period. Amplitude represents the maximum displacement of a wave from its equilibrium position. Wavelength is the distance between two consecutive points on a wave that are in phase. Therefore, the correct answer is 'Period' as it specifically refers to the time taken for a wave to complete one full cycle, distinguishing it from the other choices which represent different properties of a wave.

4. In an experiment where five tropical plants are kept at varying humidity levels in a greenhouse for three months, while one plant is left outside in normal conditions, with plant height measured weekly, what serves as the control of the experiment?

• A. Plant height for each tropical plant
• B. The plant left outside in normal conditions
• C. Humidity level readings in the greenhouse
• D. Amount of time used to study plant height

Correct answer: B

Rationale: The correct answer is B. The plant left outside in normal conditions acts as the control in the experiment. It provides a standard reference point for comparison to assess the impact of the varying humidity levels on the growth of the tropical plants. Choice A is incorrect because it refers to the dependent variable being measured, not the control. Choice C is incorrect as humidity levels in the greenhouse are part of the experimental conditions, not the control. Choice D is incorrect as the time used for studying plant height is a parameter of the experiment and not the control.

5. What substance is required to drive the sliding filament process during muscle contraction?

• A. ATP
• B. Hormone
• C. Potassium
• D. Water

Correct answer: A

Rationale: The substance required to drive the sliding filament process during muscle contraction is ATP (adenosine triphosphate). ATP provides the energy needed for muscle contraction by enabling the myosin heads to bind to actin and generate force. This energy release drives the sliding of the filaments, causing muscle fibers to contract. Hormones, potassium, and water do not directly drive the sliding filament process in muscle contraction. Hormones are signaling molecules that regulate various physiological processes but do not directly provide energy for muscle contraction. Potassium is an electrolyte important for nerve and muscle function but is not the primary driver of the sliding filament process. Water is essential for overall hydration and bodily functions but does not directly participate in the muscle contraction process.

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