Division and Differentiation Unit 1 Flashcards
What name is given to the human body cells that are not involved in reproduction ?
Somatic cells
How many chromosomes are found in somatic cells ?
46
By what process do somatic cells produce more somatic cells ?
Mitosis
What name is given to the human cells involved in producing the gametes for reproduction ?
Germline cells
How many chromosomes are found in germline cells ?
46
By what process do germline cells produce more germline cells ?
Mitosis
In which part of the body are germline cells found ?
Testes
By which process do germline cells produce the gametes (egg and sperm) ?
Meiosis
How many egg or sperm are produced when a germline cell divides by mitosis ?
4
Name two types of stem cells
Embryonic and Tissue
What word is used to describe the ability of embryonic stem cells to divide into almost any cell type ?
Pluripotent
What word can be used to describe the ability of tissue stem cells to divide into a limited range of cell types ?
Multipotent
Name 5 uses of stem cells
- Disease development
- Drug uses
- Corneal repairs
- Skin grafts
- Bone marrow transplants
What signals do cancer cells fail to respond to ?
Regulatory signals
What name is given to the abnormal mass of cells formed by uncontrolled cell division of cancer cells ?
Tumour
What do somatic cells undergo ?
Somatic cells undergo mitosis to produce more cells which are identical to the parent cell
What do germline cells undergo ?
Germline cells can divide by mitosis to form more germline cells or divide by the process of meiosis to produce haploid gametes
Where are germline cells found ?
In the reproductive organs
What is cellular differentiation ?
Cellular differentiation is the process by which a cell expresses certain genes to produce proteins characteristic for that type of cell
What happens after a cell is differentiated ?
It only expresses the genes that produce protein characteristic for that type of cell
What are stem cells ?
Stem cells are unspecialised somatic cells that have the ability to reproduce and differentiate into a diverse range of specialised cells
Products of Embryonic Stem Cells
- Found in blastocyst
- Pluripotent
Products of Tissue Stem Cells
- Found in specific areas of the body
- Multipotent
What do cancer cells do ?
Cancer cells divide excessively to produce a mass of abnormal cells (a tumour) that do not respond to regulatory signals and may fail to attach to each other
What happens if cancer cells fail to attach ?
If the cancer cells fail to attach to each other, they can spread though the body to form secondary tumours
Explain why stem cells are able to develop into different types of cells
They have the ability to switch on and off genes
Are cells involved in reproduction ?
No
Name 3 types of somatic cells
- Platelets
- Red blood cell
- Nerve cells
Are germline cells involved in reproduction ?
Yes
What is the term given to a sex cell ?
Gamete
What term is given to a cell containing 2 sets of chromosomes ?
Diploid
What is the term given to a cell containing 1 set of chromosomes ?
Haploid
What is the term used to describe 2 chromosomes which have the same genes ?
Homologous
Name a source of embryonic stem cells
Blastocyst
What is a potential ethical issue with use of embryonic stem cells ?
People view it as murder
What is a somatic cell ?
A body cell
Somatic cells form different body tissues, list some tissue types
- Muscle
- Skin
Germline cells divide by mitosis to produce what ?
More germline cells
Germline cells divide by meiosis to produce what ?
Haploid gametes
Describe the formation of secondary tumours
If the cancer cells fail to attach to each other, they can spread though the body to form secondary tumours
Three properties of stem cells
- Unspecialised
- Can differentiate into a range of cells
- Has the ability to switch on and off genes
Name two therapeutic use of stem cells
- Skin grafts
- Corneal repair
Name two locations of tissue stem cells
- Bone marrow
- Skin
Tissue stem cells found in bone marrow will develop into what ?
Blood cells