which stage of mitosis is occurring when the chromosomes gather on either side of the separating cell

HESI RN

Biology Practice Test

1. During which stage of mitosis do the chromosomes gather on either side of the separating cell?

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

Correct answer: B

Rationale: The correct answer is B, Telophase. During telophase, the chromosomes gather at opposite poles of the cell as the nuclear envelopes start to form around them, indicating the end of cell division. Choices A, C, and D are incorrect because during metaphase, the chromosomes align in the middle of the cell; in anaphase, the chromosomes separate and move towards opposite poles; and in prophase, the chromosomes condense and the nuclear envelope breaks down, respectively.

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. Which of the following correctly identifies the two types of cells?

A. Mitosis and meiosis
B. Mitochondrion and chloroplast
C. Genotype and phenotype
D. Prokaryotic and eukaryotic

Correct answer: D

Rationale: The correct answer is D: Prokaryotic and eukaryotic. Cells are classified into two major types: prokaryotic, which lack a nucleus, and eukaryotic, which have a defined nucleus and other membrane-bound organelles. Choice A, mitosis and meiosis, refers to cell division processes. Choice B, mitochondrion and chloroplast, are cell organelles involved in energy production and photosynthesis, respectively. Choice C, genotype and phenotype, relate to genetic characteristics and physical traits, not cell types.

4. The Punnett square shows that one parent carries the recessive gene for a cleft chin (c) while the other parent does not. What percentage of the parents' offspring is predicted to have a cleft chin?

A. 25%
B. 50%
C. 0%
D. 75%

Correct answer: C

Rationale: The correct answer is 0%. If one parent carries the recessive gene for a cleft chin while the other parent does not, none of the offspring will express the recessive phenotype. This is because in order for a child to have a cleft chin, they would need to inherit the recessive gene from both parents. Therefore, although the offspring could be carriers of the gene, none are predicted to have a cleft chin. Choices A, B, and D are incorrect because the presence of the recessive gene in one parent and its absence in the other would not result in any offspring showing the cleft chin trait.

5. In DNA, the nucleotide base adenine always binds with which of the following?

A. Guanine
B. Uracil
C. Thymine
D. Cytosine

Correct answer: C

Rationale: The correct answer is C: Thymine. In DNA, adenine always pairs with thymine, forming a base pair held together by hydrogen bonds. Guanine pairs with cytosine. Uracil is found in RNA, not DNA. Cytosine pairs with guanine. Therefore, option C is the correct pairing for adenine in DNA.