Unit 2 - Cell Signaling Flashcards
How do Cells send and receive signals?
Through signal transduction
What process occurs as an organism develops?
Rapid Cell Division and then diffrentiation
What are Mature Cells?
A cell which has acquired a specific function rather than general.
What are tissues in the body made from?
cells that interact with each other forming functional organs
What is a plasma membrane?
The barrier from outside and inside the cell
What is a nucleus
The internal complex which contains all of the genetic material
What are receptors?
Imbedded in the cells membrane, which receive signals
Why do cells have all the same DNA information in the nucleus, but all express differently?
Transcription factors can either turn certain genes on and off, the ones that are turned on are the ones that can be expressed in the cell
Do human cells have a high lifespan?
Yes, only ~1% actually go through mitosis
What are Embryonic cells?
Cell which is derived from an early stage of an embryo, which is able to differentiate.
How are embryonic cells produced?
Through cell division of Embryonic stem cells
What are Embryonic cells able to produce?
Adult cell types which are totipotent
–> they can differentiate into any adult cell
What is the difference between Adult cells and Embryonic cells
Embryonic cells can differentiate into type of cell type (liver, skin, eye, etc. )
==> totopotent
Adult cells can only differentiate into the cells within its tissue
==> pluripotent
How do Stem cells know when to replicate and what to replicate to?
Through a signal, and then the transduction pathway is initiated
What are stem cells?
The set of cells that are able to amplify/copy together and turn into different specialized cells
They differentiate
What is self renewal
A process stem cells go through in cell division
- When the stem cell goes through mitosis, one goes and differentiates and the other remains the stem cell
When does the cell get told to differentiate
After its parent cell went through mitosis, and its only told to that one cell
Will cells divide again when they are mature?
No, its very rare
What happens to the mature cells after a while?
they die off
How are the mature cells replaced?
through other stem cells going through differentiation and replacing them.
What is the process of cell signaling?
Receptor activation, signal transduction, response, termination
What is protein Kinase?
It is an enzyme which starts phosphorylation, activates protein target
What is the Kinase and Phosphatase rule in this class?
Phosphatase always wins
What is protein turnover
The idea that after cell life, it dies and it is re-expressed if the nucleus codes for it
What is Ubiquitin Dependent Proteolysis
The same idea of protein turnover
Ubiquitin is selectively attached to proteins
Tag tells it to go to protesome
protein is destroyed and ubiquitin is recycled
What is Receptor Mediated Endocytosis
When receptor is stuck in membrane and signal enters the receptor
Signal is collected as a vesicle and the two are separated
Divides into two vesicle, one has receptor and one has vesicle
Receptor is then entered back into the membrane
OR
Destroyed if signal no longer needed
signal is ALWAYS degraded in lysosome.
Degradation mode
Receptors are removed and the signal is destructed in the lysosome
Recycle Mode
the receptors are replaced without signal m
- the signal is destructed in the lysosome
