B2 Cell Division And Stem Cells

Question 1

How many chromosomes does human body cells and ganetes have

Answer 1

Human body - 46 chromsomes

Gametes - 23 chromosomes

Question 2

Why chromosomes in body cells are normally found in pairs

Answer 2

Each pair contains two chromosomes, one coming from each parent

Question 3

Why genetic material must be doubled during mitosis

Answer 3

So all important genetic information ends up in each of the new cells

Question 4

Situations where mitosis is occurring

Answer 4

Development and growth

Question 5

Mitosis

Answer 5

The part of the cell cycle when a eukaryotic cell divides to produce two daughter cells

Question 6

Chromosomes

Answer 6

Thin strands of DNA

Question 7

DNA

Answer 7

The chemical that makes up the genetic material of humans

Question 8

What does DNA stand for

Answer 8

Deoxyribonucleic acid

Question 9

Gene

Answer 9

A section of DNA which controls part of a cell

Question 10

Gamete

Answer 10

A sex cell

Question 11

Why mitosis is an important process in living things and how characteristics are inherited

Answer 11

Plays an important part in the development of embryos

Question 12

Growth

Answer 12

A permanent increase in size or mass

Question 13

Differentiation

Answer 13

The process a cell becomes specialised

Question 14

Importance of cell differentiation in multicellular organisms

Answer 14

They are able to perform a specialised function in the body

Question 15

Compare and contrast differentiation in plants and animals

Answer 15

Plant cells retain their ability to differentiate throughout their whole life

Animal cells are mainly restricted to repair and replacement in later life

Question 16

Why plant clones are genetically identical to each other

Answer 16

Clones contain identical sets of genetic material in the nucleus

Question 17

How using tissue culture creates a clone of a plant

Answer 17

Small groups of cells extracted from a plant and placed in a petri dish

Division of cells eventually result in formation of a clone of parent plant

Question 18

Why it is easier to clone a plant compared to an animal

Answer 18

Plant cells have a cell wall, which makes it easier to isolate and grow individual cells

Question 19

How to clone a plant

Answer 19

A branch from parent plant cut off

Leaves removed

Stem planted in damp compost

Question 20

Stem cell

Answer 20

A cell that is not differentiated

Question 21

Why embryonic stem cells are more useful for helping medical conditions

Answer 21

Embryonic stem cells can be used to regenerate or repair diseased tissue and organs

Question 22

What can plant stem cells be used for

Answer 22

To create clones

Question 23

Why plant clones are produced in the agriculture industry

Answer 23

Allows a variety of a plant with desirable characteristics to be produced cheaply, quickly and on a large scale

Question 24

How can stem cells be used to help medical conditions

Answer 24

A stem cell transplant replaces damaged blood cells with healthy ones

Can be used to treat conditions affecting the blood cells such as leukaemia and lymphoma

Question 25

Arguments for the use of stem cells

Answer 25

Can treat medical diseases

They could be used to replace cells that have been damaged or destroyed

Question 26

Arguments against the use of stem cells

Answer 26

Some people believe life begins at contraception which means the embryo is alive

They view the use of stem cells as killing an embryo

Question 27

What therapeutic cloning can be used for

Answer 27

Understanding disease and developing new treatments for disease

Question 28

Therapeutic cloning

Answer 28

A process that produces an embryo with genes that are identical to the patient’s

Question 29

Evaluate use of stem cells

Answer 29

They could be used to replace cells that have been damaged or destroyed