Part 3

Question 1

Plasma vs serum (in vitro)

Answer 1

Add plasma to culture medium…..layer of cells in petri dish remains sparce
WBC’s and platelets, RBCs during centrifugation

Add serum to culture medium…. layer of cells (fibroblasts) becomes very dense- cofluent
Blood clotting

Question 2

When a tissue is wounded

Answer 2

cells are stimulated to grow growth factors
release by the platelet at the moment of clotting
recover a wound

i.e. PDGF-BB released upon degranulation of platelets

Question 3

Tyrosine kinases

Answer 3

phosphorilate tyrosine :(

Question 4

Transmembrane domains are

Answer 4

are highly hydrophobic

Question 5

Growth factor receptors are…

Answer 5

encoded by the organism’s genome

Question 6

Some cells make the ligands for receptors that they display! This might allow cell to control its own proliferation… why?

Answer 6

Mutant receptors can fire in a ligand-independent fashion

Question 7

ECM

Answer 7

extracellular matrix

Question 8

Cell surface proteins (integrins)

Answer 8

mechanically tether cytoskeleton into ECM