Seminiferous Epithelium Composition

What is the main function of Sertoli cells in the seminiferous tubules?

To produce spermatozoa
To nurture and support developing germ cells (correct)
To regulate hormone production in the interstitial tissue
To provide structural support to the tubules

What type of cells are found in the interstitial tissue surrounding the seminiferous tubules?

Sertoli cells and SSCs
Nerve cells and capillary networks
Spermatogonia and spermatozoa
Leydig cells, macrophages, and mesenchymal cells (correct)

During development, what is the direction of primordial germ cell migration in the seminiferous tubules?

Downward towards the basement membrane (correct)
Remain stationary at the center of the tubules
Upward towards the lumen of the tubules
Laterally towards the interstitial tissue

What is the characteristic of Apaired spermatogonia?

Remain attached to each other via intercellular bridges (C) Signup and view all the answers

What is the outcome of Aaligned spermatogonia division?

Formation of 4–16 connected cells (B) Signup and view all the answers

What process do aligned spermatogonia undergo to form spermatocytes and spermatids?

Meiosis (B) Signup and view all the answers

What type of cells comprise the vertebrate hematopoietic stem cell niche?

Osteoblasts, sinusoidal endothelial cells, and bone marrow stromal cells (A) Signup and view all the answers

What is the effect of HIFs on cells?

They increase the survival of cells by decreasing oxidative stress (B) Signup and view all the answers

What promotes the survival of cancer stem cells in a hypoxic environment?

An increase in intracellular ROS (A) Signup and view all the answers

Where are hypoxic environments often found?

In tumors where cell division outpaces angiogenesis (D) Signup and view all the answers

What is a characteristic of Hematopoietic Stem Cells (HSCs)?

They can self-renew and have multipotency (A) Signup and view all the answers

What is the outcome of symmetrical cell divisions in bone marrow transplantation?

Reconstitution of the hematopoietic system (C) Signup and view all the answers

What is the effect of radiation therapy on HIF1?

It increases HIF1 amounts (B) Signup and view all the answers

What is the role of HIF1α and ROS interactions in cancer?

It induces EMT and promotes metastasis (D) Signup and view all the answers

What type of cells are produced in bone marrow that give rise to all other blood cells?

Hematopoietic Stem Cells (HSCs) (B) Signup and view all the answers

What genes are regulated by hypoxia in melanoma?

MXI1, FN1, and NME1 (D) Signup and view all the answers

What is the current limitation of human ES and EG cells in terms of blood-producing cells?

They are not able to self-renew in the long-term (B) Signup and view all the answers

What is the purpose of apoptosis in the context of HSCs?

To eliminate excess HSCs in the body (D) Signup and view all the answers

What happens when excess stem cells are injected into an animal?

They undergo apoptosis and are eliminated (A) Signup and view all the answers

What is the effect of excess numbers of stem cells in an HSC transplant?

It improves the likelihood and speed of engraftment (D) Signup and view all the answers

What is the current understanding of the mechanism behind the effect of excess stem cells in an HSC transplant?

It is not well understood and requires further research (B) Signup and view all the answers

What is the sequence of treatment for chronic myeloid leukemia described by Thomas and Clift?

Chemotherapy, interferon, bone marrow transplants (C) Signup and view all the answers

What is the main advantage of ES cells in terms of their development?

They can be easily programmed and have perfect plasticity (A) Signup and view all the answers

Why are adult somatic stem cells considered an attractive option for therapeutic applications?

They are autologous and do not pose a risk of rejection (D) Signup and view all the answers

What is the traditional concept of adult stem cell development?

A linear and irreversible progression concluding in terminally differentiated cell types (A) Signup and view all the answers

What is the term used to describe the ability of tissue-specific stem cells to acquire the fate of cell types different from the tissue of origin?

Stem cell plasticity (D) Signup and view all the answers

What is a potential risk associated with the use of ES cells?

All of the above (D) Signup and view all the answers

What is the main advantage of adult somatic stem cells compared to ES cells?

They are autologous and do not pose a risk of rejection (C) Signup and view all the answers