Nursing Elites

1. Which of the following provides support and shape to the cell?

• A. Microtubules
• B. Microfilaments
• C. Cilia
• D. Microvilli

Correct answer: A

Rationale: Microtubules are fundamental components of the cytoskeleton in a cell, playing a crucial role in providing structural support and maintaining the cell's shape. They are composed of tubulin protein subunits and are involved in various cellular processes like cell division, intracellular transport, and cell motility. Microfilaments, on the other hand, are involved in cell movement and maintaining cell shape but are not primarily responsible for supporting the cell's overall structure. Cilia and microvilli are cellular projections that aid in movement and absorption, respectively, but they do not play a significant role in providing structural support to the cell.

2. A water molecule contains two types of atoms that are covalently bonded. Which of the following makes up a water molecule?

• A. One hydrogen atom and one oxygen atom
• B. One hydrogen atom and two oxygen atoms
• C. Two hydrogen atoms and two oxygen atoms
• D. Two hydrogen atoms and one oxygen atom

Correct answer: D

Rationale: The correct answer is D: Two hydrogen atoms and one oxygen atom. A water molecule consists of two hydrogen atoms covalently bonded to one oxygen atom. This forms a stable structure known as H2O. Choice A is incorrect as water molecule contains two hydrogen atoms. Choices B and C are incorrect as they do not reflect the correct composition of a water molecule.

3. Which of the following is responsible for the synthesis of carbohydrates, lipids, and steroid hormones?

• A. Smooth endoplasmic reticulum (ER)
• B. Rough endoplasmic reticulum (ER)
• C. Golgi apparatus
• D. Ribosomes

Correct answer: A

Rationale: The smooth endoplasmic reticulum (ER) is the correct answer. It is responsible for the synthesis of lipids, including steroids, and also plays a role in carbohydrate metabolism. The rough endoplasmic reticulum (ER) is involved in protein synthesis and processing, not lipid or carbohydrate synthesis. The Golgi apparatus is responsible for modifying, sorting, and packaging of proteins and lipids, but not for their synthesis. Ribosomes are the cellular organelles responsible for protein synthesis, not lipid or carbohydrate synthesis.

4. Water is held together by which of the following bonds?

• A. Electrostatic attraction
• B. Van der Waals forces
• C. Hydrogen
• D. Oxygen

Correct answer: C

Rationale: Water molecules are held together by hydrogen bonds, which are weak bonds formed between the slightly positive hydrogen atom of one water molecule and the slightly negative oxygen atom of another. Choice A, electrostatic attraction, is a general term for the attraction between opposite charges but does not specifically describe the bonds in water. Choice B, Van der Waals forces, are weak intermolecular forces that arise from temporary fluctuations in electron distribution, not the primary bonds in water. Choice D, oxygen, is incorrect as oxygen is part of the water molecule but not the bond holding water molecules together.

5. Which of the following molecules contains the code required for replication?

• A. Deoxyribonucleic acid (DNA)
• B. Transfer RNA (tRNA)
• C. Messenger RNA (mRNA)
• D. Ribonucleic acid (RNA)

Correct answer: A

Rationale: The correct answer is A: Deoxyribonucleic acid (DNA). DNA contains the genetic information essential for replication, ensuring the accurate transmission of genetic material from one generation to the next. Choice B, Transfer RNA (tRNA), is involved in protein synthesis, not replication. Choice C, Messenger RNA (mRNA), carries genetic information from DNA to the ribosome but does not contain the code for replication. Choice D, Ribonucleic acid (RNA), is a broader category that includes both mRNA and tRNA, but the specific molecule containing the code required for replication is DNA.

Similar Questions