9.2 signal classification Flashcards
what are the 4 distance measurements of signalling?
- endocrine- large distance
- paracrine- up to 20 cells away
- autocrine- cell is the signalling and responding cell (self)
- juxtacrine- Direct physical contact
how is the final messaged at long and short distances?
far apart- signalling molecule is transported by the circulatory system
close- signalling molecule moves by diffusion.
attached- signalling cell is not released at all
what type of signalling does adrenalin use?
endocrine signalling
what is a growth factor?
a type of signalling molecule that causes the responding cel to grow, divide, or differentiate
What type of signalling is important foe the development of an embryo?
autocrine signalling and juxacrine signalling
what type of signalling is used by cancer cells to divide?
autocrine signalling
What must happen during juxtacrine signalling?
two cells in direct contact. a transmembrane protein on the surface of a cell acts as a signalling molecule, while a transmembrane on another cell acts as a receptor. the signalling cell is released but remains associated with the plasma membrane of the signalling cell