Cells and control

Question 1

when the cells containing nuclei are ready to divide, the DNA

Answer 1

copies itself then coils and condenses to form chromosomes

Question 1

For most of the time,
DNA exists in

Answer 1

The nucleus as a thin strand

Question 2

Each chromosome is made from a single molecule of

Answer 2

DNA

Question 3

Each human body cell contains

Answer 3

46 chromosomes. These can be arranged into 23 pairs.

Question 4

Cells divide when:

Answer 4

-an organism grows
-an organism becomes damaged and -needs to produce new cells for repair
-organisms like bacteria reproduce asexually

Question 5

In mitosis, two cells called

Answer 5

daughter cells are produced, each identical to the parent cell.

Question 6

Interphase

Answer 6

The cell spends most of its life in this phase. The DNA in chromosomes copies itself ready for mitosis.

Question 7

What order does mitosis happen

Answer 7

Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis

Question 8

Prophase

Answer 8

The DNA in chromosomes and their copies condenses to become more visible. The membrane around the nucleus disappears.

Question 9

Metaphase

Answer 9

Chromosomes and their copies line up in the middle of the cell.

Question 10

Anaphase

Answer 10

Chromosomes and their copies are pulled to different ends of the cell.

Question 11

Telophase

Answer 11

New membranes form around the chromosomes at each end of the cell.

Question 12

Cytokinesis

Answer 12

The cell membrane pinches in and eventually divides into two daughter cells.