The Cell Cycle and gene mutations

Question 1

Components of cell cycle

Answer 1

G1, S, G2, mitosis

Question 2

G1 phase

Answer 2

Cell grows and increases protein content and organelles’ number increases

Question 3

S phase

Answer 3

Cell replicates its DNA, ready to divide by mitosis

Question 4

G2 phase

Answer 4

Rapid cell growth and protein synthesis of proteins needed in cell division

Question 5

Stages of mitosis in order

Answer 5

Prophase, Metaphase, Anaphase, Telophase

Question 6

Prophase

Answer 6

Chromosomes condense and arranged randomly throughout cytoplasm of cell. Centrioles move to opposite ends of spindle.

Question 7

Metaphase

Answer 7

Chromosomes line up along equator of cell and attach to spindle by their centromere

Question 8

Anaphase

Answer 8

Sister chromatids pulled apart by spindle fibres by the centromere. Spindles contract moving them to opposite poles of cell, centromere first.

Question 9

Telophase

Answer 9

Chromatids reach opposite poles. Uncoil and become long and thin again. Nuclear envelope forms around each group of chromosomes and cytokinesis occurs.

Question 10

What is conjugation

Answer 10

Process of DNA being passed from one species of bacterium to another

Question 11

Process of conjugation

Answer 11

• One cell produces thin projection that meets another cell - Conjugation tube
• Donor cell replicates one of its plasmids
• Plasmid broken to make it linear, so it can pass through conjugation tube
• Recipient cell acquires new characteristics from donor cell

Question 12

Horizontal gene transmission

Answer 12

Transmission of DNA from one species of bacteria to another

Question 13

What are gene mutations?

Answer 13

Change to base sequence of DNA caused by spontaneous errors in DNA replication. Rate of mutations increased by mutagens

Question 14

How do mutagens increase rate of mutations?

Answer 14

• Acting as bases
• Altering bases
• Changing structure of DNA