Cell cycle and mitosis

Question 1

What does the cell cycle consist of?

Answer 1

a period of growth and DNA replication

Question 2

What are the stages within interphase?

Answer 2

G1, S, G2

Question 3

What happens in the G1 stage?

Answer 3

the cell grows and new organelles and cell proteins are made

Question 4

What happens in the S stage?

Answer 4

the DNA of the cell is replicated

Question 5

What happens in the G2 stage?

Answer 5

the cell grows further and continues to synthesise proteins

Question 6

What happens in mitosis (short summary)

Answer 6

a cell divides to form two genetically identical cells

Question 7

What is mitosis needed for?

Answer 7

growth and repair of body tissues

Question 8

What happens in prophase?

Answer 8

chromosomes condense
spindle fibres begin to form
nuclear envelope breaks down
chromosomes become free in cytoplasm

Question 9

What happens in metaphase?

Answer 9

chromosomes - made up from two chromatids - line up along the equator of the cell
chromosomes attach to spindle fibres by their centromeres

Question 10

What happens in anaphase?

Answer 10

chromosomes divide at the centromere separating the sister chromatids
spindle fibres contract and chromatids are pulled to the opposite poles of the cell

Question 11

What happens in telophase?

Answer 11

chromatids have reached the poles of the cell
they uncoil and become long and thin (now known as chromosomes)
a nuclear envelope forms around each set of chromosomes
cell splits into two in a process called cytokinesis