Michael Anderson Prof. Thompson EXSC 224-001 May 30th, 2016Assignment # 21) The most common Glucocorticoid secreted by Humans is cortisol. The most common Mineralocorticoid secreted by Humans is Aldosterone. Both Cortisol and Aldosterone production can be linked to the release of ACTH by the anterior pituitary gland. In times of stress, the hypothalamus releases an increased amount of CRH leading to increased production ofACTH. Therefore, both cortisol and aldosterone levels can be influenced by stress. Both glucocorticoids and mineralocorticoids act in survival situations. Aldosterone allows for the retention of sodium and water while releasing excess potassium by way of urination. This is a survival function that lowers membrane potential across the body and allows for easier action potential generation. Cortisol calls for the breakdown of various stored forms of energy to be used by the body rather than using glucose. This leaves glucose to be used solely by the brain, this too is a critical survival function in times of high stress. The after effects produced by both of these corticoids working together allows for survival in extreme or stressful situations thus wewould expect to see them happening at roughly the same times. The Hypersecretion of these corticoids causes a disease referred to as Addison’s disease. This disease is known to cause hypoglycemia, dehydration, hypertension, sodium-potassium imbalance and rapid weight loss. 2) Normal Blood Glucose level lies somewhere in the ballpark of 82 – 100 mg/ dL. The two main hormones that work to regulate blood glucose levels are insulin and glucagon.Insulin is the main hormone that lowers blood glucose levels during the period of time immediately following a meal. After eating, blood glucose levels rise above normal range triggering the secretion of insulin by the beta islet cells of the pancreas. Insulin triggers the binding of vesicles studded with Glut transport proteins to bind to the cell membranes of body cells. These proteins allow the cells to accept glucose, lowering blood glucose levels. Low insulin levels are typically caused by an acute form of type one diabetes. Insufficient insulin levels lead to consistently high blood glucose levels which can cause further damage to the beta cells in the pancreas causing further progression of the before mentioned diabetes. Glucagon is the main hormone responsible for raising blood glucose levels during the fasting period between meals. When low blood glucose levels are detected the Alpha islet cells in the pancreas secret glucagon. Glucagon triggers glycogenolysis in the liver, breaking down stored glycogen into glucose and releasing it into the blood to raise blood glucose levels. Glycogen also triggers lipolysis or the breakdown of stored lipids deposits into fuel to be used in place of glucose by body cells, saving glucose to be used by the brain in survival situations. Deficiencies in glucagon secretion can lead to Insulin-induced hypoglycemia.3) Little ol’ Billy is suffering from pituitary gigantism. The Tumor was most likely secreting growth hormone. Normally the production of growth hormone is kept in check by a negative feedback loop affecting the hypothalamus. They hypothalamus secretes Growth Hormone Releasing Hormone (GHRH) which triggers the anterior pituitary to begin secreting Growth Hormone (GH). GH is processed by other tissues such as the liver in order to produce Insulin-like growth factor, this growth factor stimulates development of skeletal muscle proliferation at the growth plates. High IGF levels feedback to the hypothalamus and stimulate itto slow the production of GHRH and begin secreting Growth Hormone Inhibiting Hormone, which slows the release of GH keeping overall growth and development at a steady and controlled pace. The tumors secretion of GH was unable to be controlled properly by the negative feedback loop so GH was secreted without regard of regulation attempts made by the hypothalamus. The continuous GH release leads to uncontrolled growth effects like enlarged face or extremities, deepening of the voice, enlarged organs and abnormal joint development which can in turn cause further discomfort and complications. The best course of action would be to remove the tumor and begin corrective hormone therapy to gain control of the situation. 4) The Blood types (A, B, AB or O) are a result of specific antigens and antibodies present in one’s red blood cells. Type A individuals possess type A antigen and type B antibodies. Type B individual’s possess type B antigen and type A antibodies. Type AB people have both A and B antigens but possess no antibodies. Type O people do not possess any antigen but have both A and B antibodies. Whether a person is blood type positive or negative is determined by whether or not RH factor is present or not. The precautions for blood transfusions are extremely important. The antibodies in one’s blood protect the body from particular antigens, for example type B antibodies detect type AB antigen. If the antibodies come in contact with their antigen it is perceived as a threat and the body tries to protect itself by beginning agglutination or “Clotting”. These clots can be dangerous as they can clog capillaries and prevent proper oxygenation which causes cell damage or