Proteins in controlling processes

• Outline 5 importances of proteins in controlling processes

  pancreas receptors in controlling BGL

  osmoreceptors in controlling WPT

  pacinian corpuscles

  T cells in immune system

  baroteceptors in detecting blood pressure
• Outline osmoreceptors in controlling WPT

  water enters osmoreceptors in hypothalamus causing them to swell. hypothalamus reduces ADH which reduces the amount of aquaporins embedded in collecting ducts (less permeable to water) so less water is reabsorbed into the blood and WPT returns to normal. without this body cells would be more succeptable to lysis and loose their function e.g. less oxygen transported by haemoglobin limiting respiration and ATP production.
• outline pacinian corpuscles in cotrolling pressure

  Pacinial corpusles detect stimuli which deforms the stretch mediated Na channels, opening them. This causes sodium ions to diffuse into the axon.if the threshold is reached an action potential will occur which stimulates adjacent sodium channel to be depolarised. if this didn't occur the CNS wouldn't receive the impulse and produce an effect e.g. muscle contraction away from the stimuli, decreasing survival chances.
• Outline pancreas in controlling high BGL

  detected by receptors on B cells. Causes the release of the hormone insulin which binds to complementry receptors on cells. When it binds it causes vesicles with glucose protein channels to fuse with the cell membrane.Causing the cell membrane to be more permeable to glucose and glucose moves into the cell via facilitated diffusion down concentration gradient. Also activates enzymes that convert glucose into glycogen and fat. More glucose is used in respiration due to the high concentration within cells. These factors cause a drop in the BGL
• outline pancreas role in controlling low BGL?

  glucagon is released, whose effects increase the blood glucose. In the liver cells glucagon binds to receptors on the cell surface membrane of liver cells. This causes a number of changes. Activates enzymes that form glucose from glycerol and amino acids and other molecules called gluconeogenesis. Activates enzymes that hydrolyse glycogen into glucose. Glucose then moves out the liver cells down the concentration gradient into the blood through protein channels. Increasing the blood glucose levels.
• why is controlling BGL important?

  glucose is a substrate for respiration producing ATP. If the concentration falls too low, cells deprived of energy, in the form of ATP, and will die. If concentration too high causes osmotic effects as water will move out the cells into blood down water potential gradient. We can see the importance by looking directly at type 11 diabetes, they produce the hormone insulin however their receptors are not responsive. Leads to a high blood sugar, causing extreme tiredness, thirst and urination as well as weight and muscle loss.
• outline receptors in controlling immune system

   In the cell mediated response T cells have receptors on their cell membrane, these are complementary to the antigens on antigen presenting cells. This causes the T cells to rapidly divide via mitosis into memory T cells used in secondary infection, form T killer cells and activate B cells by binding to complementary receptors on their cell surface membrane. This causes the B cell to rapidly divide into B memory cells for secondary response and plasma cells. Plasma cells produces lots of antibodies specific to the antigen. 
• what’s the importance of T cell receptors in the immune system?

  Without these receptors T cells would not be able to activate B cells and no antibodies would be produced. Therefore microorganisms would remain inside the organism and not be eradicated. The organism would constantly be infected by harmful microorganisms with no line of defence and undergo infections causing the organism to die.
• what do baroreceptors do if blood pressure is too high?

  Baroreceptors detect high blood pressure, sending impulse to the medulla which sends impulses along the parasympathetic neurones which secretes acetylcholine that binds to receptors on the SAN this causes the heart rate to decrease to reduce blood pressure.
• what do baroreceptors do if blood pressure is too low?

  Baroreceptors detect low blood pressure, sending impulse to the medulla which sends impulses along the sympathetic neurones which secretes noradrenaline that binds to receptors on the SAN this causes the heart rate to increase to increase blood pressure.
• what is the importance of maintaining blood pressure?

  significantly reduce the risk of heart attacks and strokes