3.7 Mitosis

Question 1

What does mitosis produce

Answer 1

Two daughter cells that have the same number of chromosomes as the parent cell and eachother

Question 2

What does meiosis produce

Answer 2

Four daughter cells, each with half the number of chromosomes of the parent cell

Question 3

Describe prophase

Answer 3

Chromosomes become visible, the nuclear envelope disintegrates, the nucleolus disappears

Question 4

Describe metaphase

Answer 4

Spindle forms and the chromosomes line up on the centre of the cell

Question 5

Describe anaphase

Answer 5

Spindle fibres attached to the centromere of chromosomes contract and the chromatids are pulled towards poles

Question 6

Describe telophase

Answer 6

Chromosomes reach poles and become indistinct. Nuclear envelope reforms, nucleolus reforms and the spindle distinegrates

Question 7

Describe the process of binary fission

Answer 7

1. The circular DNA molecule replicates and both copies attach to the cell membrane, the plasmids also replicate
2. The cell membrane begins to grow between the two DNA molecules and begins to pinch inward, diving the cytoplasm into two
3. A new cell wall forms between the two molecules of DNA, dividing the original cell into two identical daughter cells, each with a single copy of the circular DNA and variable copies of the plasmids

Question 8

Why is it essential to make exact copies of existing cells

Answer 8

1. Growth
2. Repair - If cells are damaged its important new cells are identical
3. Reproduction -