Stem cells

Question 1

what are stem cells?

Answer 1

undifferentiated cells with ability to differentiate into specialised cell types and self-renew

Question 2

what are totipotent stem cells?

Answer 2

can differentiate into all cell types, including embryonic and extra-embryonic cells

Question 3

what are pluripotent stem cells?

Answer 3

can differentiate into embryonic tissue, including all 3 germ layers, somatic cells, and germ line cells

Question 4

what are multipotent stem cells?

Answer 4

can differentiate into cells of specific lineages

Question 5

what are unipotent stem cells?

Answer 5

can only differentiate into one type of differentiated progeny , such as muscle or spermatogonial stem cells

Question 6

name some examples of multipotent stem cells

Answer 6

hematopoietic, neural, and intestinal stem cell are examples of multipotent stem cells

Question 7

what is the purpose of a bone marrow transplant?

Answer 7

• Bone marrow transplants treat blood diseases like leukemia.
• Compatibility between donor and host is essential to prevent rejection.

Question 8

How can corneal stem cells be utilized in medical treatments?

Answer 8

Corneal stem cells can be cultured and transplanted to help regrow the cornea, aiding in the treatment of corneal injuries and diseases.

Question 9

Where do embryonic stem cells come from?

Answer 9

Mouse and human embryonic stem cells (ESCs) are derived from the inner cell mass of the blastocyst, a pre-implantation stage of development

Question 10

What is induced pluripotency and how is it achieved?

Answer 10

Induced pluripotency involves reprogramming somatic cells to become pluripotent by overexpressing pluripotent transcription factors, known as Yamanaka factors

Question 11

What are organoids?

Answer 11

Organoids are 3D cell cultures that mimic key features of organs, serving as valuable models for studying organ development, diseases, and drug testing.

Question 12

What are the therapies involving multipotent stem cells?

Answer 12

• Hematopoietic stem cells can treat blood diseases like leukemia through bone marrow transplantation.
• Corneal stem cells can be cultured and transplanted to help regrow the cornea.

Question 13

What are some stem cell therapies?

Answer 13

• Bone marrow transplants using hematopoietic stem cells can treat blood diseases like leukemia.
• Corneal stem cells can be cultured and transplanted to help regrow the cornea.
• Induced pluripotency involves reprogramming somatic cells into pluripotent stem cells using Yamanaka factors.

Question 14

Compare and contrast ES cells and iPS cells.

Answer 14

• ES cells are derived from the inner cell mass of the blastocyst, while iPS cells are reprogrammed from somatic cells by overexpressing pluripotent transcription factors.
• Both ES cells and iPS cells are pluripotent and can differentiate into various cell types, but ES cells raise ethical concerns, whereas iPS cells do not.

Question 15

Give examples of stem cells in adult mammals

Answer 15

Hematopoietic stem cells in bone marrow, neural stem cells in the brain, and mesenchymal stem cells in various tissues like bone and adipose tissue

Question 16

What are the advantages of using stem cells in biological research?

Answer 16

1. Regenerative potential: Can repair damaged tissues.
2. Disease modeling: Create lab models for studying diseases.
3. Drug discovery: Test new drugs for safety and efficacy.
4. Personalized medicine: Tailor treatments based on genetics.
5. Fundamental research: Understand cell development processes.
6. Tissue engineering: Create artificial organs and tissues.
7. Gene editing: Modify cells to study genetic effects.
8. Developmental disorders: Investigate early development.
9. Reduced ethical concerns: Use induced pluripotent stem cells (iPSCs) instead of embryos

Question 17

What are the disadvantages of using stem cells in biological research?

Answer 17

1. Ethical concerns: Embryonic stem cells raise ethical dilemmas.
2. Tumor formation: Risk of forming tumors during transplantation.
3. Immune rejection: Allogeneic transplantation may cause rejection.
4. Technical challenges: Complex differentiation processes.
5. Contamination risks: Potential for unintended cell contamination.
6. Limited differentiation: Some stem cells have restricted abilities.
7. Cost and time: Expensive and time-consuming research.
8. Long-term safety: Safety concerns in certain therapies.
9. Regulatory challenges: Compliance with varying regulations