protein synthesis begins with a process known as transcription where does this process occur

HESI RN

Biology Practice Test

1. Protein synthesis begins with a process known as transcription. Where does this process occur?

A. In the cytoplasm
B. In the nuclear envelope
C. In the ribosome unit
D. In the nucleus

Correct answer: D

Rationale: The correct answer is D: In the nucleus. Transcription, the initial step of protein synthesis, takes place in the nucleus where DNA is transcribed into mRNA. This mRNA then leaves the nucleus and enters the cytoplasm where translation occurs on the ribosomes. Choices A, B, and C are incorrect because transcription specifically occurs in the nucleus, not in the cytoplasm, nuclear envelope, or ribosome unit.

2. Which of the following best describes phenotype?

A. The hereditary potentials and limitations of an individual
B. The genetic makeup of an individual organism
C. The entire complex of genes inherited from both parents
D. All the observable characteristics of an organism

Correct answer: D

Rationale: The correct answer is D: 'All the observable characteristics of an organism.' Phenotype refers to all the observable characteristics of an organism, such as physical appearance, behavior, and other traits, which result from the interaction of its genotype with the environment. Choice A is incorrect because it describes genotype. Choice B is incorrect as it defines genotype, not phenotype. Choice C is incorrect as it refers to the genotype, the genetic information inherited from both parents, rather than the observable traits.

3. Which of the following makes it possible to predict the genotype and phenotype of the offspring of sexual reproduction?

A. Punnett square
B. Chi-square
C. Microscope
D. None of these

Correct answer: A

Rationale: The correct answer is A, Punnett square. A Punnett square is a tool specifically designed to predict the genotype and phenotype combinations of offspring resulting from a particular cross or breeding experiment. It helps in understanding the probability of different genotypes and phenotypes appearing in the offspring. Choice B, Chi-square, is a statistical test used to determine if there is a significant difference between the expected frequencies and the observed frequencies in a study. Choice C, Microscope, is used for viewing tiny structures and organisms, not for predicting genetic outcomes. Choice D, None of these, is incorrect as Punnett square is a valid tool for predicting genetic outcomes in offspring.

4. Which of the following is not true of mitosis?

A. Mitosis produces daughter cells
B. Mitosis has five main stages
C. Mitosis can only be done by haploids
D. Following mitosis, daughter cells are identical to parent cells

Correct answer: C

Rationale: The correct answer is C. Mitosis occurs in diploid cells and involves stages that result in the production of two identical daughter cells. Haploids do not undergo mitosis, as mitosis is a process specific to diploid cells. Choice A is true as mitosis does produce daughter cells. Choice B is incorrect as mitosis typically consists of four main stages: prophase, metaphase, anaphase, and telophase. Choice D is true, as one of the main outcomes of mitosis is the production of daughter cells that are genetically identical to the parent cell.

5. Where can ribosomes be found inside a cell?

A. Attached to the endoplasmic reticulum (ER) and in the cytoplasm
B. Within the cellular membrane
C. Attached to the Golgi apparatus and in the cytoplasm
D. Within the nucleus

Correct answer: A

Rationale: Ribosomes can be found attached to the endoplasmic reticulum (ER) or free-floating in the cytoplasm. The correct answer is A because ribosomes are responsible for synthesizing proteins and are commonly found on the ER or in the cytoplasm. Choice B is incorrect because ribosomes are not typically located within the cellular membrane. Choice C is incorrect as ribosomes are not attached to the Golgi apparatus; instead, they are involved in protein synthesis. Choice D is incorrect as ribosomes are not found within the nucleus but rather in the cytoplasm or attached to the ER.