| what is a totipotent cell | the cell that it divides into can become any cell in the body |
| embryonic stem cells | some of the cell start to develop the placenta, the cells are not able to make placenta cells as they have already diferentiated. |
| what is pluripotent cells | can divide and form any other cell in the body except the placenta cell |
| what is in adults | dont have any totipotent and pluripotent stem cells, they only have adult stem cells |
| what happens when the adult stem cells divide | the daughter cells could differentiate into a variety of cells (closely related) --> multipotent (the capacity to self-renew by dividing and to develop into multiple specialised cell types present in a specific tissue or organ.) |
| what happens when the 2 daughter cells are produced | one of the daughter cells could differentiate, whilst the other can stay an adult stem cell |
| what is cancer | uncontrolled cell division |
| when division happens what needs to happen | needs to be controlled, proto-oncogenes help regulate that, after cell division it stops. tumor-suppressor genes --> prevent any further cell division. |
| what happens to the proto-oncogene in cancer | it mutates and becomes an oncogene, cell growth and division become uncontrolled |
| what happens to the tumor-suppressor genes in cancer | they stop working, so nothing stops the cell cycle, uncontrolled cell division, end up with a large mass of cells named a tumor |
| what is contact inhibitation | as a cell is dividing and it comes into contact with other cells, contact inhibation triggers it to stop dividing. |
| what happens with contact inhibitation in cancer | it doesnt work, so the tumour can just get bigger and bigger |
| 2 types of tumors? | benign (stays in one place)
malignat (can spread to other parts of the body to form secondary tumours) |
| common misconception for stem cells | used to replace damaged cells, not repair |
