T2

Question 1

What are stem cells?

Answer 1

Master cells with the ability to develop into over 200 different cell types

Stem cells can grow, divide, and differentiate into specialized cells.

Question 2

Define cell renewal.

Answer 2

The continuous process where old cells are replaced with new ones to maintain balance

This process can accelerate with injury or slow down with aging.

Question 3

What is homeostasis?

Answer 3

The body’s ability to maintain internal balance despite external changes.

Question 4

How often are red blood cells replaced?

Answer 4

Every 6 weeks by hematopoietic stem cells (HSCs) in the bone marrow.

Question 5

What is the typical replacement cycle for skin cells?

Answer 5

Replaced frequently by epithelial stem cells in the basement layer.

Question 6

How long does it take for the entire skeleton to be replaced?

Answer 6

Every 6-8 years through osteoclasts and osteoblasts.

Question 7

What new evidence exists regarding cardiomyocytes?

Answer 7

Shows slow turnover with only half being replaced by age 50.

Question 8

What is self-renewal in stem cells?

Answer 8

The capacity to divide and produce identical copies while remaining undifferentiated.

Question 9

Differentiate between symmetrical and asymmetrical division.

Answer 9

Symmetrical division produces two identical daughter cells; asymmetrical division produces two non-identical daughter cells.

Question 10

What is a stem cell niche?

Answer 10

A specialized location where stem cells are maintained and supported by nearby cells.

Question 11

What does proliferation refer to in stem cells?

Answer 11

The process where stem cells multiply to produce more cells.

Question 12

Define apoptosis.

Answer 12

Programmed cell death controlled by enzymes called caspases.

Question 13

What is potency in stem cells?

Answer 13

The potential of a stem cell to differentiate into different cell types.

Question 14

What are totipotent stem cells?

Answer 14

Stem cells that can form an entire organism, such as a fertilized oocyte.

Question 15

What defines pluripotent stem cells?

Answer 15

Can give rise to any cell type in the body but not to extra-embryonic tissues.

Question 16

What are multipotent stem cells?

Answer 16

Stem cells that can develop into several but not all cell types, e.g., blood stem cells.

Question 17

Define oligopotent stem cells.

Answer 17

Stem cells that can differentiate into a few cell types.

Question 18

What are unipotent stem cells?

Answer 18

Stem cells that can only differentiate into one type of cell.

Question 19

What is characterization of stem cells?

Answer 19

The process of testing stem cells to confirm their properties.

Question 20

What techniques are used to identify stem cells based on surface proteins?

Answer 20

Flow Cytometry and FACS (Fluorescence-Activated Cell Sorting).

Question 21

What is RT-PCR?

Answer 21

A technique used to analyze gene expression by isolating mRNA from stem cells.

Question 22

What are embryonic stem cells (ESCs)?

Answer 22

Stem cells derived from embryos fertilized in vitro, raising ethical concerns.

Question 23

What are induced pluripotent stem cells (iPS)?

Answer 23

Adult cells reprogrammed to behave like embryonic stem cells.

Question 24

Where are hematopoietic stem cells (HSCs) found?

Answer 24

In the bone marrow, responsible for forming all blood cells.

Question 25

What can mesenchymal stem cells (MSCs) differentiate into?

Answer 25

Bone, cartilage, and fat cells.

Question 26

What is transdifferentiation?

Answer 26

The phenomenon where a stem cell differentiates into a cell type outside its expected lineage.

Question 27

What is the mesengenic process?

Answer 27

The plasticity of mesenchymal stem cells (MSCs) to differentiate into various tissue types.

Question 28

What are some clinical applications of stem cells?

Answer 28

Treating Type I diabetes, spinal cord injuries, multiple sclerosis, and cardiac conditions.

Question 29

What challenges exist in stem cell therapy?

Answer 29

Ethical issues, risks of genetic instability in iPS cells, and complexity in inducing pluripotency.

Question 30

What is cloning in the context of stem cells?

Answer 30

Includes reproductive and therapeutic cloning to create isogenic stem cells.

Question 31

True or False: The field of human cloning has faced scandals involving false claims.

Answer 31

True.