Question 1

According to the Central Dogma of molecular biology, which of the following correctly describes the flow of genetic information in a eukaryotic cell?

Accepted Answer

DNA → mRNA → Protein

Question 2

During DNA replication, which enzyme is responsible for synthesizing the RNA primer required to initiate synthesis of the new DNA strand?

Accepted Answer

Primase

Question 3

In the replication fork diagram, which strand is synthesized continuously and in the same direction as the replication fork movement?

Accepted Answer

Leading strand

Question 4

Which of the following events occurs during prophase of mitosis?

Accepted Answer

Chromosomes condense and spindle fibers begin to form

Question 5

Which of the following is NOT a source of genetic variation in meiosis?

Accepted Answer

DNA replication during S phase

Question 6

A couple, both carriers for a recessive genetic disorder, have two children. What is the probability that both children will be affected by the disorder? (Assume independent assortment and that the disorder is autosomal recessive.)

Accepted Answer

$$0.25 	imes 0.25 = 0.0625$$

Question 7

During RNA splicing, which regions are removed from the pre-mRNA transcript?

Accepted Answer

Introns

Question 8

Which site on the ribosome does a tRNA molecule exit after its amino acid has been added to the growing polypeptide chain?

Accepted Answer

E site

Question 9

If a DNA template strand runs 3' to 5' from the promoter region, in which direction will RNA polymerase synthesize the mRNA?

Accepted Answer

5' to 3'

Question 10

Which of the following best describes the function of the S phase in the cell cycle?

Accepted Answer

DNA replication

Question 11

Which of the following statements about Okazaki fragments is correct?

Accepted Answer

They are short DNA fragments synthesized on the lagging strand during DNA replication

Question 12

Which of the following is a function of transcription factors in eukaryotic cells?

Accepted Answer

They bind to promoter regions to help initiate transcription

Question 13

During meiosis I, which event is responsible for the segregation of alleles according to Mendel's law?

Accepted Answer

Separation of homologous chromosomes during anaphase I

Question 14

Which of the following is true about the directionality of mRNA during translation?

Accepted Answer

mRNA is read from 5' to 3' direction

Question 15

Which of the following is NOT a phase of mitosis?

Accepted Answer

S phase

Question 16

A cell is observed to have chromosomes lined up in the middle of the cell, but the homologous pairs are not together. Which stage is this cell most likely in?

Accepted Answer

Metaphase of mitosis

Question 17

Which of the following best explains why meiosis, but not mitosis, leads to genetic variation?

Accepted Answer

Meiosis includes crossing over and independent assortment

Question 18

Which of the following is the correct sequence of events in the cell cycle?

Accepted Answer

G1 → S → G2 → M

Question 19

Which of the following statements about exons and introns is correct?

Accepted Answer

Exons are expressed and exit the nucleus as part of mature mRNA

Question 20

If a cell starts with 8 chromosomes, how many chromosomes will each daughter cell have after mitosis and after meiosis II, respectively?

Accepted Answer

8 after mitosis, 4 after meiosis II

Core Concepts of the Central Dogma, Cell Division, and Genetic Variation

Guida di studio - Domande di pratica

Study guide - Flashcard