Ch 3, 5 Cell enviroment interactions

Question 1

what does the cell environment include?

Answer 1

glycoproteins, proteins of glycocalyx
cell adhesion molecules (CAMs)
Membrane receptors

Question 2

Roles of CAM

Answer 2

1. anchor cells to extracellular matrix or to each other
2. assist in movement of cells past each other
3. CAMS of blood vessel lining attract WBC to injured or infected areas
4. stimulate synthesis or degradation of adhesive membrane junctions
5. transmit intracellular signals to direct cell migration, proliferation and specialization
   ++important to embryotic development

Question 3

Roles of membrane receptors

Answer 3

1. contact signalling-touching and recognition of cells, in normal development and immunity
2. chemical signaling- interaction between receptors and ligands (neurotransmitters, hormones) to alter activity of cell proteins (enzymes or chemically gated ion channels)
3. G protein- linked receptors- ligand binding activates a G protein, affecting an ion channel oe enzyme or causing the release of an internal second messenger, such as cyclic AMP