Nursing Elites

1. What macromolecules are formed from amino acids, and what are their roles?

• A. Lipids; store energy
• B. Carbohydrates; provide energy
• C. Proteins; perform various functions like catalysis, transport, and structural support
• D. Nucleic acids; store genetic information

Correct answer: C

Rationale: The correct answer is C. Proteins are macromolecules formed from amino acids and have diverse roles, such as serving as enzymes, transport molecules, and providing structural support. They are essential for catalysis, cellular communication, immune response, and many other functions in living organisms. Choices A, B, and D are incorrect. Lipids are not formed from amino acids but from fatty acids and glycerol, mainly serving as energy storage molecules. Carbohydrates are composed of sugars and provide energy to the body. Nucleic acids, like DNA and RNA, are made up of nucleotides and store genetic information in cells.

2. Unlike the circulatory system, the lymphatic system does not have a pump. How does lymph move through the lymphatic vessels?

• A. By the pumping action of the heart
• B. Due to muscle contractions and breathing movements
• C. Through one-way valves within the vessels
• D. All of the above

Correct answer: C

Rationale: Lymph moves through the lymphatic vessels primarily due to muscle contractions and breathing movements and also with the help of one-way valves within the vessels. The lymphatic system lacks a central pump like the heart; hence, it relies on the contraction of surrounding muscles and breathing movements to propel lymph fluid. One-way valves within the lymphatic vessels prevent backflow and ensure the unidirectional flow of lymph. Option A is incorrect as the lymphatic system does not rely on the pumping action of the heart. Option D is incorrect as the correct answer is the combination of muscle contractions, breathing movements, and one-way valves, not all the options provided.

3. Which type of muscle is responsible for moving the skeleton?

• A. Cardiac muscle
• B. Skeletal muscle
• C. Smooth muscle
• D. Voluntary muscle

Correct answer: B

Rationale: Skeletal muscle is the correct answer as it is responsible for moving the skeleton. Skeletal muscles are under voluntary control, meaning they can be consciously controlled by the individual. Cardiac muscle (Choice A) is found in the heart and is responsible for pumping blood, not moving the skeleton. Smooth muscle (Choice C) is found in internal organs and is responsible for involuntary movements like digestion. Voluntary muscle (Choice D) is not a specific type of muscle; it refers to muscles that can be consciously controlled, which includes skeletal muscles.

4. Which organelle in the cell is responsible for protein synthesis?

• A. Ribosome
• B. Nucleus
• C. Mitochondrion
• D. Golgi apparatus

Correct answer: A

Rationale: The correct answer is A: Ribosome. Ribosomes are the organelles responsible for protein synthesis in the cell. They are the cellular machinery where translation, the process of assembling proteins from amino acids based on mRNA sequences, occurs. Ribosomes can be found floating freely in the cytoplasm or attached to the endoplasmic reticulum. The nucleus (choice B) houses DNA but is not directly involved in protein synthesis. Mitochondria (choice C) are responsible for energy production through cellular respiration, not protein synthesis. The Golgi apparatus (choice D) is involved in modifying, sorting, and packaging proteins for secretion, not in the synthesis of proteins.

5. In a closed system with a gas at constant volume, what will happen to the temperature if the pressure is increased?

• A. The temperature will stay the same
• B. The temperature will decrease
• C. The temperature will increase
• D. It cannot be determined with the information given

Correct answer: C

Rationale: In a closed system with a gas at constant volume, according to Gay-Lussac's law, the temperature of a gas is directly proportional to its pressure. When the pressure is increased, the temperature of the gas will also increase. This relationship is a direct consequence of the ideal gas law, where pressure and temperature are directly proportional when volume is held constant. Therefore, as pressure increases in a closed system with constant volume, the temperature of the gas will increase. Choices A, B, and D are incorrect. The temperature will not stay the same (Choice A) or decrease (Choice B) when the pressure is increased in this scenario. The relationship between pressure and temperature in a closed system with constant volume allows for a definitive conclusion about the increase in temperature when pressure is increased, making Choice D, which suggests inability to determine, incorrect.

Similar Questions