Nursing Elites

1. Which of the following is a lipid that is a membrane component and a precursor to significant hormones?

• A. Nucleic acids
• B. Proteins
• C. Carbohydrates
• D. Steroids

Correct answer: D

Rationale: The correct answer is D, Steroids. Steroids are a type of lipid that function as essential components of cell membranes and serve as precursors for significant hormones like estrogen and testosterone. Nucleic acids (choice A) are not lipids but are molecules like DNA and RNA that store genetic information. Proteins (choice B) and carbohydrates (choice C) are biomolecules but are not lipids and do not serve as precursors for hormones or membrane components.

2. Proteins are polymers of 20 molecules called:

• A. Amino acids
• B. Phospholipids
• C. Carbohydrates
• D. Fatty acids

Correct answer: A

Rationale: Proteins are indeed polymers made up of amino acids. Amino acids are the building blocks of proteins, where each protein has a unique sequence of amino acids that determines its structure and function. Phospholipids, carbohydrates, and fatty acids are not molecules that make up proteins. Phospholipids are the main components of cell membranes, carbohydrates are sugars used for energy and structural purposes, and fatty acids are building blocks of lipids.

3. In the hierarchy of biology, cells combine to form which of the following?

• A. Macromolecules
• B. Molecules
• C. Tissues
• D. Organelles

Correct answer: C

Rationale: In the hierarchy of biology, cells combine to form tissues. Tissues are groups of cells that work together to perform specific functions. This is a fundamental level of organization above individual cells but below organs and organ systems. Macromolecules and molecules are smaller components that make up cells, not what cells combine to form. Organelles are structures within cells that perform specific functions and do not result from the combination of cells.

4. The bilayer of the cellular membrane consists of phospholipids with all except which of the following scattered throughout?

• A. Nucleic acids
• B. Cholesterol
• C. Proteins
• D. Glycoproteins

Correct answer: A

Rationale: The cellular membrane is composed of a phospholipid bilayer with cholesterol, proteins, and glycoproteins distributed throughout. Nucleic acids are not found within the cellular membrane. Cholesterol helps maintain membrane fluidity, while proteins and glycoproteins play important roles in cell signaling, transport, and structural support.

5. What is the primary method of asexual reproduction used by most bacteria?

• A. Meiosis
• B. Mitosis
• C. Binary fission
• D. Interphase

Correct answer: C

Rationale: The correct answer is C: Binary fission. This is the main process through which most bacteria reproduce asexually. During binary fission, a single cell divides into two identical cells, each containing a copy of the genetic material. Choices A and B, meiosis and mitosis, are processes involved in sexual reproduction and are not used by bacteria for asexual reproduction. Choice D, interphase, is a stage of the cell cycle where the cell prepares for division and is not a method of reproduction.

Similar Questions