Nursing Elites

1. The formula for calculating heart rate is HR = (220 - age) * 0.65. If a patient's heart rate is 136.5, what is their age?

• A. 30
• B. 40
• C. 50
• D. 60

Correct answer: B

Rationale: Rearrange the formula to solve for age: age = 220 - (HR / 0.65). Substitute the heart rate (136.5) to get 40 years old.

2. During which phase of the cardiac cycle do the atria contract, pushing blood into the ventricles?

• A. Atrial diastole
• B. Ventricular systole
• C. Atrial systole
• D. Ventricular diastole

Correct answer: C

Rationale: The correct answer is C: Atrial systole. During the cardiac cycle, the atria contract during atrial systole, pushing blood into the ventricles. This phase occurs after atrial diastole when the atria fill with blood. Ventricular diastole (option D) is when the ventricles relax and fill with blood, preparing for ventricular systole (option B), which is when the ventricles contract to pump blood out of the heart. Atrial systole is crucial for ensuring efficient filling of the ventricles before they contract, making it a key phase in the cardiac cycle.

3. The hormone responsible for milk production in the breasts after childbirth is:

• A. Estrogen
• B. Prolactin
• C. Oxytocin
• D. Relaxin

Correct answer: B

Rationale: The correct answer is B: Prolactin. Prolactin is the hormone responsible for milk production in the breasts after childbirth. It is produced by the pituitary gland and stimulates the alveoli in the breasts to produce milk. Estrogen plays a role in breast development during pregnancy but is not responsible for milk production. Oxytocin is responsible for the ejection of milk from the breasts during breastfeeding. Relaxin is a hormone that helps prepare the body for childbirth by relaxing the ligaments in the pelvis. Therefore, the hormone directly responsible for milk production after childbirth is prolactin.

4. What property of a substance refers to its ability to undergo a chemical change and form new substances with different properties?

• A. Density
• B. Mass
• C. Reactivity
• D. Volume

Correct answer: c

Rationale: Reactivity refers to a substance's ability to undergo a chemical change or reaction, forming new substances with different properties.

5. Where does cellular respiration, the process of converting chemical energy into ATP, take place in eukaryotic cells?

• A. Nucleus
• B. Ribosomes
• C. Mitochondria
• D. Golgi apparatus

Correct answer: C

Rationale: Rationale: Cellular respiration, the process of converting chemical energy into ATP, takes place in the mitochondria of eukaryotic cells. The mitochondria are known as the powerhouse of the cell because they are responsible for generating most of the cell's ATP through the process of cellular respiration. This process involves the breakdown of glucose and other organic molecules to produce ATP, which is the primary energy currency of the cell. The other organelles listed in the options (nucleus, ribosomes, and Golgi apparatus) do not play a direct role in cellular respiration.

6. Which of the following is NOT a recognized mode of natural selection?

• A. Directional selection (favoring one extreme trait value on a spectrum)
• B. Disruptive selection (favoring both extreme trait values on a spectrum)
• C. Stabilizing selection (favoring the average trait value on a spectrum)
• D. Sexual selection (selection based on mate choice that influences reproductive success)

Correct answer: D

Rationale: Rationale: A) Directional selection is a recognized mode of natural selection where one extreme trait value on a spectrum is favored over others. This can lead to a shift in the average trait value over time. B) Disruptive selection is a recognized mode of natural selection where both extreme trait values on a spectrum are favored over the average trait value. This can lead to the population splitting into two distinct groups. C) Stabilizing selection is a recognized mode of natural selection where the average trait value on a spectrum is favored over extreme values. This can lead to a reduction in genetic diversity within a population. D) Sexual selection is not a mode of natural selection in the traditional sense, as it involves mate choice and competition for mates rather than direct selection pressure on traits that affect survival and reproduction in the environment. Sexual selection can lead to the evolution of traits that enhance an individual's ability to attract

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