Stem cells 2.1.6 (j,k,l,m)

Question 1

what is the process of a cell becoming specialised?

Answer 1

differentiation

Question 2

what is a stem cell?

Answer 2

an undifferentiated cell which can differentiate into a range of specialised cell types

Question 3

what can a differentiated cell not do?

Answer 3

re-enter the cell cycle
so it cannot divide

Question 4

why are stem cells important?

Answer 4

they are a source for new cells needed for:
- growth
- development
- tissue repair

Question 5

what are the three types of cell potency?

Answer 5

totipotent
pluripotent
multipotent

Question 6

what is potency?

Answer 6

a stem cell’s ability to differentiate

Question 7

what is totipotent?

Answer 7

a stem cell can differentiate into any type of cell

Question 8

what is pluripotent?

Answer 8

a stem cell can differentiate into all tissue types but not whole organisms

Question 9

what is multipotent?

Answer 9

a stem cell can only differentiate into a range of cells in a specific tissue

Question 10

where are blood cells derived from from?

Answer 10

the bone marrow

Question 11

what happens at the bone marrow?

Answer 11

adult stem cells divide and differentiate to replace worn out blood cells:
- erythrocytes
- neutrophils

Question 12

what are the sources of animal stem cells?

Answer 12

• embryonic stem cells
• adult stem cells

Question 13

what are embryonic stem cells?

Answer 13

found in the embryo

are totipotent from early on

after 7 days they become pluripotent

Question 14

what are adult stem cells?

Answer 14

found in the bone barrow

are multipotent

Question 15

what is the source of stem cells in plants?

Answer 15

meristematic tissue

Question 16

where is meristematic tissue found?

Answer 16

between the phloem and xylem

Question 17

what are the properties of stem cells in the meristematic tissue?

Answer 17

pluripotent

can differentiate into xylem and phloem cells

Question 18

what are the uses of stem cells?

Answer 18

• treating diabetes
• treating Alzheimers
• treating Parkinsons
• developmental biology

Question 19

how are stem cells used to treat diabetes?

Answer 19

stem cells are differentiated into beta cells which can replace damaged beta cells and allow for insulin to be produced

Question 20

how are stem cells used in developmental biology?

Answer 20

they are used to study how organisms grow and develop

Question 21

what ethical issues surround the use of embryonic stem cells?

Answer 21

to harvest embryonic stem cells, the embryo must be destroyed

many people view the destruction of embryos as murder as people see the creation of an embryo as the start of life