Stem Cells Flashcards
This is a primitive cell that can either self-renew or give rise to more specialized cell types. They differentiate into multiple, functional cell types.
Stem cells
Stem cells functionally reconstitute a given tissue _______. For example, one blood stem cell gives rise to red cells, white cells, and platelets.
In vivo
What are the characteristics of stem cells?
- Not terminally differentiated
- Can divide without limit
- Undergo slow division
When stem cells divide, what happens?
Give rise to 1 cell with stem cell characteristics and the other with the ability to be differentiated.
Adult stem cells are _______ specific.
Tissue
This type of potency is the ability to give rise to all cells of an organism, including embryonic and extraembryonic tissues (cells which support embryonic development).
Totipotency
What is an example of totipotency?
Zygote
This type of potency is the ability to give rise to all cells of the embryo and subsequently adult tissues (embryonic stem cells).
Pluripotency
***i.e., Blastocyst of embryo
This type of potency is the ability to give rise to different cell types of a given lineage (adult stem cells).
Multipotency
***i.e., tissues from endoderm, ectoderm, and mesoderm
In these stem cells, the proportions of body parts are determined early. Each tissue has a fixed number of these cell populations. Programmed to have a fixed number of divisions controlled by short range signals that operate for a few hundred cell diameters. Defines size of large final structures.
Founder stem cells
This type of cell are cells that divide frequently. They move from a cell with stem cell characteristics to a differentiated cell and leave the basal layer and incorporate into the layers above.
Transit amplifying cells
Transit amplifying cells are programmed to have a limited number of divisions (finite), which part of the strategy for growth control. They are _________.
Committed
For a steady pool of stem cells, half of daughter cells must remain as stem cells to retain original DNA. This is accomplished by…
Divisional asymmetry
Environmental asymmetry
This is the term for an asymmetric division that may create 2 cells, one with stem cell characteristics and another with factors that give it the ability to differentiate.
Divisional asymmetry
This is the term for a division that makes 2 identical cells but environment may influence/alter one cell.
Environmental asymmetry
This is the term for the idea that some tissues stem cells selectively retain original DNA, which is a way to prevent genetic errors in stem cells. When divided, one daughter cell will retain the stem cell characteristics and the original strand of DNA is preserved in stem cells from generation to generation. The second cells gets the newly synthesized strand.
Immortal strand hypothesis
Embryonic stem cells are (PLURIPOTENT/MULTIPOTENT), meaning they can become any cell in the body. Adult stem cells are undifferentiated and generate cell types in the tissues in which they reside, making them (PLURIPOTENT/MULTIPOTENT).
Pluripotent
Multipotent