AP BIO FR Ch. 45

Question 1

2 pancreatic hormones and describe their effect

Answer 1

Insulin-lowers blood glucose level

Glucagon-increases blood glucose level

Question 2

Explain insulin and its target cells, reception, transduction, response

Answer 2

Target cells: Any cell except red blood cells
Reception: Insulin binds to tyrosine kinase on the cell surface. The tyrosine kinase is phosphorylated by the ligand binding of monomers near it.
Transduction: Binding of a signaling molecule stimulates a cascade pathway that is medicated by a secondary messenger such as cAMP and amplifies its signal
Response: The transduced signal triggers an action by the target cell such as increasing cellular uptake of glucose

Question 3

Compare steroid and protein hormones

Answer 3

Steroid (lipid-soluble): It acts as the ligand that binds to cytosol receptors. It’s main action is to alter gene expression in the target cell by entering cell through the plasma membrane
Protein (water-soluble): Alters gene expression in target cell by binding to a receptor protein such as tyrosine kinase. Has brief, but dramatic actions