Cell division & Mitosis

Question 1

What is mitosis

Answer 1

Cell division that produces genetically identical cells

Question 2

Sum up mitosis

Answer 2

Parent cell divides to produce two identical daughter cells (exact copy of DNA)

Question 3

What are 3 needs for mitosis

Answer 3

Growth of multicellular organisms
-
Repairing damaged tissue
-
Asexual reproduction

Question 4

Define gametes

Answer 4

Male/female sex cells

Question 5

What is the process that joins gametes

Answer 5

Fertilisation

Question 6

What does fertilisation produce

Answer 6

A zygote

Question 7

How many chromosomes do normal cells have

Answer 7

46 (set of 23 from each parent)

Question 8

How many chromosomes do gametes have

Answer 8

One set (23)

Question 9

Name 4 key parts of ovum structure

Answer 9

• Cell (plasma) membrane
• Follicle cells
• Zona pellucida
• Nucleus

Question 10

Function of follicle cells?

Answer 10

Form protective coating

Question 11

Function of Zona pellucida

Answer 11

Protective glycoprotein layer (sperm have to penetrate)

Question 12

Why is there lots of mitochondria in sperm

Answer 12

Releases energy in from of ATP, which sperm use to swim

Question 13

5 main parts of sperm structure

Answer 13

-Nucleus
-Cell (plasma) membrane
-Acrosome
-Flagellum
-Lots of
Mitochondria

Question 14

Function of acrosome

Answer 14

Contains digestive enzymes to break done Zona pellucida

Question 15

Function of flagellum

Answer 15

Allows sperm to swim toward egg cell

Question 16

Where does the sperm have to go to?

Answer 16

Through the cervix and uterus into one of the oviducts

Question 17

Where does fertilisation occur

Answer 17

The oviduct

Question 18

What is meiosis

Answer 18

A type of cell division that happens in the reproduce organs

Question 19

How many chromosomes do cells that divide by mitosis have?

Answer 19

The full number (46) to start with

Question 20

How many chromosomes do cells that are formed from meiosis have

Answer 20

Half the number (23)

Question 21

What is the main difference between meiosis and mitosis

Answer 21

Meiosis produces cells that are genetics different

Question 22

How does genetic variation occur?

Answer 22

Independent assortment of chromosomes

Question 23

Describe G1 of interphase

Answer 23

Cell grows:

• more cytoplasm
• more organelles
• larger energy store

Question 24

Describe S stage of interphase

Answer 24

DNA replicates

Question 25

Describe G2

Answer 25

Centrioles replicate

Question 26

Describe prophase

Answer 26

1) chromosomes condense
2) centrioles move to poles, forming spindle network
3) nuclear envelope breaks down

Question 27

Describe metaphase

Answer 27

Chromosomes (2 chromatids) line up along middle of cell
&
Become attaches to spindles by their centromeres

Question 28

Describe anaphase

Answer 28

1) Centromeres divide
2) spindles contract, pulling chromatids to poles
3) appears V shape

Question 29

Describe telophase

Answer 29

1) Chromatids reach opposite ends, uncoil and become long and thin again
2) nucleus envelope forms around each group of chromosomes
3) 2 daughter cells are now formed

Question 30

Where does meiosis occur

Answer 30

Reproductive organs

Question 31

In what two ways does meiosis produce genetically different cells

Answer 31

1. Crossing over of chromatids

2. Independent assortment