which of the following is the term used to represent alternative versions of a gene

HESI RN

Biology Practice Test

1. Which of the following is the term used to represent alternative versions of a gene?

A. Alleles
B. Binary fission
C. Heterozygous
D. Homozygous

Correct answer: A

Rationale: The correct answer is A: Alleles. Alleles are different versions of a gene that can exist at a specific locus on a chromosome. This term specifically refers to the different forms of a gene that can exist. Choices B, C, and D are incorrect because they do not represent alternative versions of a gene. Binary fission is a form of asexual reproduction in single-celled organisms, while heterozygous and homozygous refer to the genetic makeup of an individual rather than alternative versions of a gene.

2. Which of the following organelles is known as the cell's digestion center?

A. Chloroplasts
B. Mitochondria
C. Lysosomes
D. Ribosomes

Correct answer: C

Rationale: The correct answer is C: Lysosomes. Lysosomes contain enzymes that break down waste materials and cellular debris within the cell, making them the cell's digestion center. Choice A, Chloroplasts, are responsible for photosynthesis. Choice B, Mitochondria, are the powerhouse of the cell, generating energy. Choice D, Ribosomes, are involved in protein synthesis. Therefore, Lysosomes are specifically known for their role in digestion within the cell.

3. Which of the following options correctly lists the five stages of mitosis in order from beginning to end?

A. Prophase, Prometaphase, Telophase, Metaphase, Anaphase
B. Prophase, Prometaphase, Metaphase, Anaphase, Telophase
C. Metaphase, Anaphase, Prophase, Prometaphase, Telophase
D. Metaphase, Telophase, Anaphase, Prophase, Prometaphase

Correct answer: B

Rationale: The correct order of the stages of mitosis is Prophase, Prometaphase, Metaphase, Anaphase, and Telophase. Choice A is incorrect because it has Anaphase and Metaphase in the wrong order. Choice C is incorrect as it starts with Metaphase, which is not the first stage of mitosis. Choice D is incorrect as it also has the stages in the wrong order, and it starts with Metaphase, which is incorrect.

4. During photosynthesis in green plants, light energy is captured and used to convert all except which of the following into oxygen and energy-rich organic compounds?

A. Minerals
B. Water
C. Carbon dioxide
D. Metals

Correct answer: D

Rationale: During photosynthesis in green plants, light energy is utilized to convert water and carbon dioxide into oxygen and energy-rich organic compounds like glucose. Minerals play a role in plant growth but are not directly converted during photosynthesis. Metals are not part of the photosynthesis process, making them the correct answer. Therefore, the correct choice is D. Choices A, B, and C are incorrect as minerals, water, and carbon dioxide are involved in the photosynthesis process.

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.