stem cells

Question 1

When a cell differentiates and becomes specialized, what ability does it lose?

Answer 1

The capacity to form alternative cell types.

Question 2

What are the two key qualities of stem cells?

Answer 2

potency (they have the capacity to differentiate into specialized cells) and self-renewal (they can continuously divide and differentiate)

Question 3

How many main types of stem cells in human development are there?

Answer 3

Four.

Question 4

What does totipotent mean?

Answer 4

the cells can create any type of cell (as well as extra-embryonic (placental) tissue) e.g. zygote- a fertilized egg

Question 5

What does pluripotent mean?

Answer 5

the cells can form any cell type (e.g. embryonic stem cells)

Question 6

What can multipotent stem cells do?

Answer 6

the cells can differentiate into a number of closely related cell types (e.g. hematopoietic adult stem cells) different types of blood cells

Question 7

What is the feature of unipotent stem cells?

Answer 7

those can not differentiate but are capable of self-renewal (e.g. progenitor cells, muscle stem cells, skin cells)

Question 8

What is the major symptom of Stargardt disease?

Answer 8

Progressive vision loss caused by the death of photoreceptors in the central portion of the retina.

Question 9

What exactly is the reason for the death of photoreceptors?

Answer 9

A specific mutation of a gene called ABCA4, causing a membrane protein used for active transport to malfunction.

Question 10

What are the advantages of using embryonic stem cells?

Answer 10

• mainly unlimited growth potential

- less chance of genetic damage

Question 11

What are the disadvantages of using embryonic stem cells?

Answer 11

• more risk of becoming tumor cells
• they are likely to be genetically different from the adult receiving the tissue
• removal of the cells kills the embryo

Question 12

What are the pluses of obtaining stem cells from the cord?

Answer 12

• they are easily obtained and stored
• the cord is removed anyway (no waste)
• fully compatible with the tissues of the adult that grows from the baby

Question 13

What are the minuses of using cord stem cells?

Answer 13

• limited capacity to differentiate

- limited quantities of stem cells from the baby’s cord

Question 14

What are the good sides of using adult stem cells?

Answer 14

• decreased risk of malignant tumors developing

- fully compatible with the adult’s tissues

Question 15

What are the drawbacks of using adult stem cells?

Answer 15

• difficult to obtain
• lesser growth potential
• limited capacity to differentiate