Cell Division (MITOSIS & MEIOSIS)

Question 1

State the definition of Cell Division

Answer 1

New cells are produced by old cells dividing.

Question 2

What is the purpose of Mitosis?

Answer 2

Growth and repair of body cells

Question 3

What is the purpose of Meiosis?

Answer 3

Production of Specialised Sex Cells

Question 4

What is Ploidy?

Answer 4

Refers to the number of complete sets of chromosomes in a cell or organism.

Diploid (2n)
Haploid (n)

Question 5

What is a Homologous Chromosome?

Answer 5

Chromosomes of the same size and shape that carry the same type of genes

Question 6

What is a Chromatid?

Answer 6

One of the two duplicated chromosomes connected at the centromere

Question 7

What is a Centromere?

Answer 7

Region of chromosome where microtubules attach during mitosis and meiosis

Question 8

What in the nucleus carries the genetic material and what is it made out of?

Answer 8

Chromosomes made out of protein and single molecule of deoxyribonucleic acid

Question 9

The Cell Cycle comprises of:

Answer 9

Interphase:
- G1
- S
- G2

Mitosis:
- Prophase
- Metaphase
- Anaphase
- Telophase

Cytokinesis

Question 10

Describe Interphase

Answer 10

Cell carries out normal functions but also prepares to divide

S Phase: Cell’s DNA unravelled and replicated, to double its genetic content

During G1 and G2: The organelles are also replicated so it has spare ones, and its ATP content is increased (ATP provides energy for cell division)

Question 11

What is Mitosis?

Answer 11

Refers to the process of nuclear division that occurs before a cell physically divides in 2.

Question 12

Explain what happens during Prophase

Answer 12

Chromosomes condense and become visible.

Centrioles move to opposite ends of cells forming network called Spindle.

Nuclear envelope breaks down and chromosomes lie in free cytoplasm

Question 13

Explain what happens during Metaphase

Answer 13

Chromosomes line up along middle of cell.

Spindle attaches to Centromere

Question 14

Explain what happens during Anaphase

Answer 14

Centromere divides, separating each pair of sister chromatids.

Spindle contracts pulling chromatids to opposite poles

Chromatids appear V-Shaped

Question 15

Explain what happens during Telophase

Answer 15

Chromatids reach opposite poles on spindle.

They uncoil and become long and thin and are called chromosomes

Nuclear envelope forms again to form 2 nuclei

Cytoplasm divides and there are two identical daughter cells.

Question 16

Name One SIMILARITY and Two DIFFERENCES between Mitosis and Meiosis

Answer 16

S: Similar cell divisions

D: Mitosis = two identical daughter cells (diploid)

D: Meiosis = four genetically different cells (haploid)

Question 17

What happens during Meiosis I?

Answer 17

First Mitotic division

Recombination exchanges segments between homologues

Produces two haploid cells with chromatids attached

Question 18

What happens during Meiosis II?

Answer 18

Second meiotic division

Sister chromatids separate into separate cells

Produces 4 recombined haploid cells