Question

Choose one out of paracrine signalling, endocrine signalling, autocrine signalling and direct signalling and describe briefly the process by which this occurs. Pick a representative signal molecule from the pathway you have chosen and indicate its function, the type of cell in which it is made and the specific manner in which it acts as a signalling molecule, including the receptor that it binds to. For example if you chose the endocrine signalling pathway you could consider looking at a hormone such as insulin. You would describe the cells from which insulin is secreted and state the overall role of insulin in the body. In signalling pathways, each signal molecule has a receptor that it binds to, so you would indicate what the receptor for insulin is called and what immediate outcome the binding of insulin has to that receptor that is. in the case of insulin, which regulates glucose uptake in the body, does the receptor directly interact with glucose or is it just part of a much larger signalling cascade

Answer 1

& Choose one out of paracrine signalking , endocrine signalling. auto crine signalling and direct signalling and diserite briefly the prouss by which this occurs. Pick a representative signal molecule from the pathway you have choose and indicate its function, the type of call in which it is made and the specife manner in which it acts as a signalling molemle, including the reuptor that it binds to .. Answer: ENDOCRINE SIGNALLING : - A gland involved in endocrine signalling specifically releases HORMONES into the bloo bloodstream. → Examples of glands include the ils lets of Langerhans in the pancrease by the Pitnitary gland interprets the signals and then itself release the appropiate chemical Signals and urnally a hormone Here, INSULIN (5123,5 208 Da) the horinne Cell synthenn : - Insulin is synthesized in significant quantition only in lp - cells in the pancrease - when ß-cell is appropriately stimulated, insulin is secreted from the cell by exocytosis and diffuses into is let capillary blood. - c peptide is also secreted inte blood, but has no known biological activity Role of insulin, - It helps control lood glucose the Ltd LIVER and MUSCLE and level fat cell by signalling to take

- in glucose from the - Insulin therefore blood. helps cells to take in glucose to te wed for energy. Signalling molecule: - Insuline activates the insulin receptor tyrosine kinase (IR) which phosphorylates and recruits different adaptors such as IRs family of Pretum - Insulin has several effects in liver which stimulate glycogen synthen. • first it activates the enzyme hexoki nase, which phosphorylates glucose , ta trapping it within the cell. Coincidently, insulin acts to inhibit the activity of glucose - 6-phosphatase Immediate ontome: Insulin finds to its reuptor (1) start many prostem activation Cascade (1) translocation of Glut-4- transporter to the plasma membrane and influx of ghose (m) glycogen synthem (1) glycolysis () fatty acid synthesis

What regulate glucose uptake! in body - Insulin mediates glucose uptake into adipose dissue and skeleton muscle through GLUT-4 glucose transporters. - GLUT-4 glucose transporters are mobilized to the Plasma memb pane by insulin stimulation, thereby af effecting glucose transport into the cell Receptor interact ghuon directly - Affer food, glucose level rises. - the rise in ghelose trigger panerease the release insulin into the blood stream - Insulin towels through the blood to our body an - It tells the cells to open up and the let the ghee in but to there is no direefly interaction with receptor and gluose.