Question 1

Which phase of the cell cycle is primarily responsible for the synthesis of DNA, and what is the main event that occurs during this phase?

Accepted Answer

S phase; DNA replication

Question 2

A patient has type AB blood. Which of the following statements best explains the inheritance pattern of the ABO blood group system?

Accepted Answer

It is an example of codominance, where both A and B alleles are fully expressed.

Question 3

During which stage of mitosis do sister chromatids separate and move toward opposite poles of the cell?

Accepted Answer

Anaphase

Question 4

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

Accepted Answer

$8$

Question 5

Which enzyme is responsible for unwinding the DNA double helix during replication?

Accepted Answer

Helicase

Question 6

A woman with genotype $I^A I^B$ for the ABO blood group marries a man with genotype $I^O I^O$. What are the possible blood types of their children?

Accepted Answer

A and B only

Question 7

Which of the following best describes the principle of independent assortment?

Accepted Answer

Alleles for different traits segregate independently during gamete formation.

Question 8

A genetic cross between two heterozygous individuals ($Aa 	imes Aa$) for a trait controlled by simple dominance will result in what expected phenotypic ratio?

Accepted Answer

$3:1$

Question 9

Which scientist(s) used X-ray crystallography to help determine the double helix structure of DNA?

Accepted Answer

Rosalind Franklin

Question 10

Which of the following is NOT a function of the cell cycle checkpoints?

Accepted Answer

To allow uncontrolled cell division in cancer cells

Question 11

A man with genotype $I^A I^O$ (blood type A) and a woman with genotype $I^B I^O$ (blood type B) have a child. What is the probability that their child will have blood type O?

Accepted Answer

$0.25$

Question 12

Which of the following best describes incomplete dominance?

Accepted Answer

The heterozygote shows a phenotype intermediate between the two homozygotes.

Question 13

Which of the following is a real-world example of pleiotropy?

Accepted Answer

Sickle cell anemia, where a single gene affects multiple traits such as red blood cell shape and resistance to malaria

Question 14

Which of the following statements about DNA replication is correct?

Accepted Answer

DNA polymerase adds nucleotides to the 3' end of the growing DNA strand.

Question 15

Which of the following best explains why cancer cells can divide uncontrollably?

Accepted Answer

They ignore signals that normally regulate the cell cycle.

Question 16

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

Accepted Answer

G1 → S → G2 → M

Question 17

Which of the following is a consequence of nondisjunction during meiosis?

Accepted Answer

Formation of gametes with abnormal numbers of chromosomes

Question 18

Which of the following best describes the role of cyclin-CDK complexes in the cell cycle?

Accepted Answer

They regulate progression through different phases of the cell cycle.

Question 19

Which of the following is a key difference between prophase I of meiosis and prophase of mitosis?

Accepted Answer

Chromosomes condense in both, but crossing over occurs only in prophase I of meiosis.

Question 20

Which of the following best describes the function of DNA ligase during DNA replication?

Accepted Answer

It joins Okazaki fragments together on the lagging strand.

General Biology Exam 4 Study Guide: Cell Cycle, Mendelian Genetics, and Molecular Basis of Inheritance

Study Guide - Practice Questions

Study Guide - Flashcards