Help please!
1. Describe the features of a target cell that makes it receptive to a particular signalling molecule
2. How do secondary messengers and G-Proteins affect signal transduction within the cell?
3. Insulin is a hydrophilic signalling molecule. It creates secondary messenger Tyroxin kinase. How does this protein amplify the response within the cell by initiating phosphorylation of protein?
4. What is the difference between antigen and immunogen (so confusing...)
Cheers everyone
Hey it might be good to know that specific details of the G-protein and secondary messenger pathways are not necessary according to the study design.
1. The necessary information to know is that signalling molecules (like most you study) are specific,hence the molecule must have the complementary structure to bind to the target cell's receptors.
3. I'd simply state that because insulin is hydrophilic, it cannot pass through the semi-permeable cell membrane (phospholipid bilayer), so the insulin receptors are on the membrane. When the ligand binds to the extracellular recpetor, it triggers a cascade of reactions (don't have to know reactions) which amplifies the response(usually to open ion channels ect).
4. Immunogens are antigens that elicit an immune response within an organism's immune system. Antigens aren't necessarily immunogens though, they are molecules (protein) that can bind to a product of an immune response (antibody).
I think the fourth question is a bit irrelevant as the difference is very little, and the second and third questions are not really within the range of the study design, although I'm not really sure.
I hope this correctly answers your queries, also if I made a mistake then pls point it out