specialised cells and stem cells 2.5B, 2.6B

Question 1

what is a stem cell?

Answer 1

all cells begin as stem cells

stem cells are not specialised to a particular job but can either:
- divide multiple times by mitosis to make new cells
or
- differentiate (develop new features) to become specialised cells, which are cells that have structures and proteins needed to carry out specific jobs in the organism

Question 2

what is stem cell differentiation controlled by?

Answer 2

genes

Question 3

what happens during differentiation?

Answer 3

genes are switched off so they cannot be transcribed, this ensures that the only proteins produced in the specialised cell are the ones needed to carry out its particular job

Question 4

what are the two types of stem cells?

Answer 4

embryonic stem cells
adult stem cells

Question 5

what are embryonic stem cells?

Answer 5

they are found in the early form of the embryo
they can differentiate into any type of cell

Question 6

what are adult stem cells?

Answer 6

cells present in some tissues in organisms
there are several different types, they divide via mitosis and each type of stem cell can differentiate into a few different types of specialised cell
CANT turn into any cell type

for example:
bone marrow stem cells can only form blood and bone cells

Question 7

how can stem cells be used in medicine or research?

Answer 7

embryos/adult stem cells can be grown in a lab to produce genetically identical cloned cells and made to differentiate into specialised cells

Question 8

how can adult stem cells be used to cure disease?

Answer 8

medicine already uses adult stem cells to cure diseases

for example, stem cells transferred from bone marrow can replace faulty blood cells to a patient

Question 9

how can embryonic stem cells be used to cure disease?

Answer 9

could also be used to replace faulty cells in sick people

for example, you could make insulin-producing cells for people with diabetes
nerve cells for people paralysed by spinal injuries and so much more

Question 10

what risks are involved in stem cell treatments?

Answer 10

stem cells grown in the lab may become contaminated with a virus and could be passed on to patients making them sicker

Question 11

why are some people against stem cell research?

Answer 11

• feel that human embryos shouldn’t be used for experiments since each one is a potential humans life