Nursing Elites

1. Which of the following organs is part of the central nervous system?

• A. Heart
• B. Brain
• C. Liver
• D. Lungs

Correct answer: B

Rationale: The correct answer is B: Brain. The brain is a vital organ that is part of the central nervous system, along with the spinal cord. It plays a crucial role in processing information, controlling body functions, and coordinating responses to stimuli. The heart, liver, and lungs are not part of the central nervous system; they belong to the cardiovascular and respiratory systems, respectively. The heart is part of the cardiovascular system, responsible for pumping blood throughout the body. The liver is part of the digestive system, involved in processes like detoxification and metabolism. The lungs are part of the respiratory system, facilitating the exchange of oxygen and carbon dioxide during breathing.

2. What do isotopes of the same element have in common?

• A. Identical number of protons and neutrons.
• B. Identical chemical properties.
• C. Identical number of electrons.
• D. Identical mass number.

Correct answer: D

Rationale: Isotopes of the same element have the same number of protons, which defines the element, but different numbers of neutrons. This difference in neutron count results in isotopes of the same element having different mass numbers. Chemical properties are determined by the arrangement of electrons in an atom, so isotopes of the same element may exhibit slightly different chemical behaviors due to different neutron numbers. The number of electrons can vary in isotopes, affecting their charge. However, the mass number, which is the sum of protons and neutrons, is the same for isotopes of the same element. Therefore, the correct answer is that isotopes of the same element share an identical mass number.

3. Where does mRNA translation typically occur?

• A. On the ribosome
• B. In the nucleus
• C. In the cytoplasm
• D. On the smooth endoplasmic reticulum

Correct answer: A

Rationale: mRNA translation typically occurs on the ribosome. Ribosomes are the cellular machinery responsible for protein synthesis. They read the mRNA sequence and assemble amino acids into a polypeptide chain during translation. The correct answer is A. Choices B, C, and D are incorrect. The nucleus is where mRNA is transcribed from DNA, while translation occurs in the cytoplasm on ribosomes. The smooth endoplasmic reticulum is involved in protein processing and transport but not in mRNA translation.

4. What is the feedback mechanism in the endocrine system that helps maintain hormone balance?

• A. Positive feedback, where a hormone stimulates its own release
• B. Negative feedback, where a hormone suppresses its own release
• C. Cascade effect, where one hormone triggers the release of another
• D. Dual hormone system, where two hormones work together

Correct answer: B

Rationale: In the endocrine system, negative feedback is the mechanism by which hormone levels are regulated. When hormone levels reach a certain threshold, they signal the body to stop producing more of that hormone, thus maintaining a balance. Negative feedback (option B) is the correct answer as it helps in preventing overproduction of hormones by suppressing their own release. Positive feedback (option A) would lead to an excessive production of hormones, disrupting the balance. The cascade effect (option C) involves one hormone triggering the release of another but does not directly regulate hormone levels. The dual hormone system (option D) refers to two hormones working together but does not specifically address the feedback mechanism for maintaining hormone balance.

5. Which organ stores and concentrates bile?

• A. Liver
• B. Gallbladder
• C. Pancreas
• D. Stomach

Correct answer: B

Rationale: The correct answer is B: Gallbladder. The gallbladder is the organ that stores and concentrates bile produced by the liver. Bile is essential for the digestion of fats in the small intestine. The liver produces bile, which is then stored and concentrated in the gallbladder until it is released into the small intestine when needed. Choices A, C, and D are incorrect because the liver produces bile, the pancreas produces digestive enzymes, and the stomach is primarily involved in the digestion of food through acid secretion and mechanical processes, not in storing bile.

Similar Questions