which of the following statements is true if a molecule has adhesion

HESI RN

Biology Practice Test

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. What is the science of biological classification commonly called?

A. Taxonomy
B. Physiology
C. Botany
D. Zoology

Correct answer: A

Rationale: Taxonomy is the science of naming, defining, and classifying groups of biological organisms based on shared characteristics. Physiology (choice B) is the study of the functions and processes of living organisms, not classification. Botany (choice C) is the study of plants, while Zoology (choice D) is the study of animals. Therefore, the correct answer is Taxonomy (choice A).

4. Prophase is the first stage of mitosis. Which of the following best describes chromosomes during this stage?

A. They are gathered on either side of the separating cell
B. They are all aligned along the metaphase plate
C. They are attached to the spindle
D. They are visibly separate

Correct answer: D

Rationale: The correct answer is D. During prophase, the chromosomes condense and become visible as distinct structures under a microscope. Choice A is incorrect as chromosomes are not gathered on either side of the separating cell during prophase. Choice B is incorrect because chromosomes align along the metaphase plate during the subsequent stage, metaphase. Choice C is incorrect as chromosomes become attached to the spindle fibers during prometaphase, the stage following prophase.

5. The term pleiotropy is best defined as which of the following?

A. A situation in which one gene remains unexpressed
B. One gene influencing multiple, seemingly unrelated phenotypic traits
C. Two genes affected by a single allele
D. A condition in which multiple genes are missing

Correct answer: B

Rationale: Pleiotropy is best defined as one gene influencing multiple, seemingly unrelated phenotypic traits. This phenomenon showcases the multifunctionality of genes, where a single gene can have effects on various aspects of an organism's phenotype. Choices A, C, and D do not accurately capture the concept of pleiotropy. Option A refers to gene expression, not pleiotropy. Option C describes genetic interactions but not in the context of pleiotropy. Option D talks about missing genes, which is unrelated to the definition of pleiotropy.