Nursing Elites

1. Which of the following nucleic acids carries amino acids to organelles called ribosomes, where the amino acids are linked one by one to produce a polypeptide?

• A. DNA
• B. mRNA
• C. rRNA
• D. tRNA

Correct answer: D

Rationale: tRNA is the correct answer as it carries amino acids to the ribosomes during protein synthesis. Transfer RNA (tRNA) plays a crucial role in protein synthesis by bringing specific amino acids to the ribosome according to the mRNA sequence. Once at the ribosome, the amino acids are linked together to form a polypeptide chain. This process is essential for the creation of proteins in the cell, highlighting the significance of tRNA in the translation process. Choice A, DNA, is incorrect as DNA does not directly participate in protein synthesis. Choice B, mRNA, is incorrect as mRNA carries the genetic information from DNA to the ribosome but does not directly carry amino acids. Choice C, rRNA, is incorrect as ribosomal RNA is a component of the ribosome structure and is involved in protein synthesis but does not carry amino acids like tRNA.

2. An object is moving in a circle at constant speed. Is there a net force acting on it?

• A. Yes, always
• B. No, never
• C. Only if its speed is changing
• D. Only if its direction is changing

Correct answer: D

Rationale: When an object is moving in a circle at a constant speed, there is a net force acting on it. This net force is directed towards the center of the circle and is responsible for continuously changing the direction of the object's velocity, even though the speed remains constant. Therefore, the correct answer is D because the net force is required to change the direction of the object's motion in a circular path. Choices A, B, and C are incorrect because the presence of a net force is necessary to continuously change the object's direction as it moves in a circular path, irrespective of changes in speed.

3. What is glucagon, where is it produced, and what is its function?

• A. Produced in the liver, releases glucose
• B. Produced in the pancreas, raises blood sugar
• C. Produced in the pancreas, lowers blood sugar
• D. Produced in the adrenal glands, regulates stress response

Correct answer: B

Rationale: Glucagon is a hormone produced in the pancreas and functions to raise blood sugar levels. It does so by signaling the liver to release stored glucose into the bloodstream. Therefore, the correct answer is B, 'Produced in the pancreas, raises blood sugar.' Choices A, C, and D describe functions or locations of other hormones, not glucagon. Glucagon is specifically released by alpha cells in the pancreas, making option B the correct choice.

4. Which gland in the endocrine system is responsible for the production of red blood cells?

• A. Pituitary gland
• B. Thyroid gland
• C. Thymus gland
• D. None of the above

Correct answer: D

Rationale: Red blood cells are not produced by any of the glands listed in the options. Instead, red blood cells are produced in the bone marrow. The pituitary gland is known as the 'master gland' and controls several other endocrine glands but is not responsible for red blood cell production. The thyroid gland regulates metabolism and growth, not red blood cell production. The thymus gland is responsible for the production of T-cells, which are a type of white blood cell involved in the immune response. The parathyroid gland regulates calcium levels in the body, not red blood cell production. Therefore, none of the glands listed are responsible for the production of red blood cells.

5. Which structure in the digestive system absorbs the most nutrients?

• A. Stomach
• B. Small intestine
• C. Large intestine
• D. Esophagus

Correct answer: B

Rationale: The small intestine is the primary site where the absorption of nutrients from digested food occurs. Its large surface area, specialized cells, and villi play key roles in maximizing nutrient absorption, making it the structure in the digestive system that absorbs the most nutrients. The stomach's main function is to break down food with acid and enzymes, not absorb nutrients. The large intestine primarily absorbs water and electrolytes, not nutrients. The esophagus is a muscular tube that connects the throat with the stomach and does not play a role in nutrient absorption.

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