Differntiation And Division

Question 1

What is a somatic cell?

Answer 1

Any body cell other than a cell involved in reproduction

Somatic cells divide by mitosis to form more somatic cells.

Question 2

What are germline cells?

Answer 2

• Haploid gametes
• Sperm and ova
• Stem cells that divide to form gametes

Germline stem cells divide by mitosis to produce more germline cells and by meiosis to produce gametes.

Question 3

What is a stem cell?

Answer 3

An unspecialised somatic cell which can divide to make copies of itself and/or differentiate into specialised cells

Stem cells can self-renew and differentiate.

Question 4

How do somatic cells divide?

Answer 4

By mitosis

Mitosis preserves the diploid number of chromosomes.

Question 5

What is the diploid number of chromosomes in human somatic cells?

Answer 5

46

These are arranged as 23 pairs of homologous chromosomes.

Question 6

What process do germline cells undergo to produce gametes?

Answer 6

Meiosis

Meiosis involves two divisions that separate homologous chromosomes and chromatids.

Question 7

True or false: Mutations in germline cells are passed to offspring.

Answer 7

TRUE

Mutations in somatic cells are not passed to offspring.

Question 8

What is cellular differentiation?

Answer 8

The process by which an unspecialised cell changes to carry out a specific function

This occurs through gene expression.

Question 9

What do differentiated cells have?

Answer 9

A specific function

They are unable to become any other type of cell.

Question 10

How does a stem cell differentiate into a skin cell?

Answer 10

By switching on genes that code for specific proteins and switching off others

This process allows the cell to develop specialised functions.

Question 11

What are tissue stem cells?

Answer 11

Stem cells found in specific tissues that are able to form various cell types

They are involved in growth and repair.

Question 12

What are embryonic stem cells?

Answer 12

Unspecialised somatic cells in animals that can self-renew and differentiate into specialised cells

They have the potential to become any cell type.

Question 14

What are tissue stem cells involved in?

Answer 14

• Growth
• Repair
• Renewal of cells

Tissue stem cells are responsible for maintaining the health of specific tissues, such as blood stem cells in the bone marrow.

Question 15

What types of cells can blood stem cells form?

Answer 15

• Red cells
• Lymphocytes
• Phagocytes
• Platelets

Blood stem cells are multipotent and can develop into a limited range of cell types.

Question 16

What are embryonic stem cells capable of?

Answer 16

• Differentiating into any type of cell

Embryonic stem cells are pluripotent and can make all differentiated cell types of the body.

Question 17

Under the right conditions, embryonic stem cells can _______ to form more embryonic stem cells.

Answer 17

self-renew

This ability is crucial for potential treatments for injury and disease.

Question 18

What are the main body tissue types?

Answer 18

• Epithelial
• Connective
• Muscle
• Nerve

The body’s organs are formed from a variety of these tissue types.

Question 19

True or false: Embryonic stem cells can only differentiate into a limited range of cell types.

Answer 19

FALSE

Embryonic stem cells are pluripotent and can differentiate into any type of cell.

Question 20

What is the role of stem cell research?

Answer 20

• Understanding gene regulation
• Studying differentiation
• Investigating cell growth

Stem cell research provides insights into fundamental biological processes.

Question 21

What are the two main uses of stem cells in research?

Answer 21

• Model cells to observe disease development
• Drug testing of potential medications

Stem cell research provides valuable information on gene regulation, differentiation, and cell growth.

Question 22

List the therapeutic uses of stem cells.

Answer 22

• Repair damaged corneas
• Repair and regenerate damaged skin following a burn

These applications demonstrate the potential of stem cells in medical treatments.

Question 23

The use of embryonic stem cells raises ethical issues because they come from _______.

Answer 23

embryos that are destroyed

This ethical concern is significant in discussions about stem cell research.

Question 24

Regulations regarding stem cell use ensure compliance with _______ law.

Answer 24

UK

These regulations guarantee that procedures for procuring stem cells are conducted safely.

Question 25

What is a **tumour**?

Answer 25

A mass of abnormal cells produced by excessive division of cancer cells ## Footnote Tumours do not respond to regulatory signals and may spread to form secondary tumours.

Question 26

True or false: Cancer cells respond to regulatory signals and attach to one another.

Answer 26

FALSE ## Footnote Cancer cells fail to attach to each other, allowing them to spread throughout the body.