Nursing Elites

1. Which of the following statements is true if a molecule exhibits adhesion?

• A. Two molecules of the same substance have the ability to stay bonded to one another
• B. The molecule has the ability to bond to or attract other molecules
• C. A molecule has the ability to increase its heat when necessary
• D. The molecule has the ability to form hydrogen bonds

Correct answer: B

Rationale: The correct statement is that if a molecule exhibits adhesion, it has the ability to bond to or attract other molecules. Adhesion refers to the ability of a molecule to bind to or attract different types of molecules. Choice A is incorrect because adhesion is about bonding to different molecules, not the same substance. Choice C is incorrect as adhesion does not relate to the ability of a molecule to increase its heat. Choice D is incorrect because forming hydrogen bonds is a specific type of interaction and not a general characteristic of molecules exhibiting adhesion.

2. Which of the following molecules acts as the genetic code's messenger?

• A. RNA
• B. Proteins
• C. DNA
• D. Carbohydrates

Correct answer: A

Rationale: The correct answer is RNA. RNA, particularly mRNA, serves as the messenger that carries genetic information from DNA to the ribosome, where proteins are synthesized. Proteins (choice B) are not the genetic code's messenger; they are synthesized based on the information carried by RNA. DNA (choice C) stores the genetic information but does not directly act as the messenger. Carbohydrates (choice D) are not involved in transmitting genetic information.

3. 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.

4. What function does cholesterol, a phospholipid, serve within the cell membrane?

• A. It builds up fats to make the structure more flexible
• B. It allows protein channels to form
• C. It makes the structure very rigid and impermeable
• D. It stabilizes the membrane structure

Correct answer: D

Rationale: Cholesterol helps to maintain the fluidity and stability of the cell membrane by fitting between the phospholipid molecules. Choice A is incorrect because cholesterol does not build up fats in the cell membrane. Choice B is incorrect as protein channels are formed by proteins, not cholesterol. Choice C is incorrect as cholesterol actually helps regulate the fluidity of the membrane, making it less rigid and more permeable.

5. In which of the following does cellular respiration take place?

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

Correct answer: B

Rationale: The correct answer is B, Mitochondrion. Cellular respiration occurs in the mitochondria, where glucose is converted into energy through a series of metabolic processes. Choice A, Golgi apparatus, is incorrect as it is involved in modifying, sorting, and packaging proteins. Choice C, Chloroplast, is incorrect as it is the site of photosynthesis in plant cells, not cellular respiration. Choice D, Ribosome, is incorrect as it is responsible for protein synthesis, not energy production through cellular respiration.

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