Division and Differentiation of Human Cells

Question 1

What are somatic cells

Answer 1

Any cell in the human body not involved in reproduction

Question 2

Are somatic cells diploid or haploid and how many sets of chromosomes do they have

Answer 2

somatic cells are diploid and contain two sets of homologous chromosomes

Question 3

how many pairs of chromosomes do diploid cells in human have

Answer 3

23 pairs of homologous chromosomes

Question 4

what do somatic cells divide by and to form what

Answer 4

somatic cells divide by mitosis to form more somatic cells

Question 5

what are germline cells

Answer 5

Germline cells are stem cells that divide to form gametes (sperm and ova)

Question 6

What do germline cells divide by

Answer 6

germline cells divide by both mitosis and meiosis

Question 7

Why do germline cells divide by mitosis

Answer 7

They divide by mitosis to produce more germline cells

Question 8

Why do germline cells divide by meiosis

Answer 8

They divide by meiosis to produce haploid gametes

Question 9

Nucleus of germline stem cells divide by mitosis for what

Answer 9

They divide by mitosis to maintain the diploid chromosome number

Question 10

Nucleus of germline stem cells divide by meiosis by

Answer 10

in two divisions
1) separating homologous pairs of chromosomes

2) separating pairs of chromatids

Question 11

how many single chromosomes do haploid gametes contain

Answer 11

haploid gametes contain 23 single chromosomes

Question 12

What is cellular differentiation

Answer 12

Cellular differentiation is the process of which cells express certain genes to produce proteins characteristic for that type of cell

Question 13

What does cellular differentiation do

Answer 13

Cellular differentiation allows cells to carry out specialised functions

Question 14

Give two types of stem cells in mammals

Answer 14

Embryonic stem cells
Tissue stem cells

Question 15

What are embryonic stem cells

Answer 15

pluripotent cells
(meaning cells in the very early embryo can differentiate into all types of cells)

Question 16

Why can embryonic stem cells divide into any type of cell

Answer 16

All genes in embryonic stem cells can be switched on and off allowing them to differentiate into any cell

Question 17

What are tissue stem cells involved in

Answer 17

Growth, repair and renewal of cells found in that tissue

Question 18

What are tissue stem cells

Answer 18

Tissue stem cells are multipotent (meaning they can only differentiate into types of cells found in that particular tissue, examples: blood stem cells found in bone marrow can develop into red blood cells, platelets, phagocytes and lymphocytes

Question 19

What are the uses for stem cells

Answer 19

Stem cells have two uses
- therapeutic uses
- research uses

Question 20

What are the therapeutic uses of stem cells

Answer 20

Therapeutic uses of stem cells are:
- Repair of damaged or diseased organs and tissues

Question 21

What are stem cells used in

Answer 21

stem cells can be used in:
- corneal repair
- regeneration of damaged skin

Question 22

How do embryonic stem cells grow

Answer 22

Embryonic stem cells can be cultured in laboratories to self - renew and provide supply of embryonic stem cells

Question 23

What are the terms of research use for stem cells

Answer 23

Stem cells can be used for research uses like:
- being used as model cells to study how diseases develop
- used for drug testing

Question 24

What will stem cell research show

Answer 24

Stem cell research provides information on how cell processes work such as cell growth and differentiation

Question 25

What is the use for embryonic stem cells

Answer 25

Embryonic stem cells can offer effective treatments for disease or injury
however
it raises ethical issues as it means destroying an early embryo

Question 26

What is different about cancer cells

Answer 26

Cancer cells divide excessively and do not respond to regulatory signals

Question 27

What results in tumours

Answer 27

Uncontrolled cell division or cancer cells result in mass of abnormal cells called tumours

Question 28

How do cancer cells spread throughout body

Answer 28

Cells within tumours may fail to attach to each other, spreading through the body where they may form secondary tumours.