MIND BLOWING TIME!: De-extinction We may now have the technology to clone extinct species and (literally) bring them back to life on this planet! Scientists have pinpointed around 20 species for which this may be possible, including the Wooly Mammoth, the Tasmanian tiger and the Dodo. Scientists, geneticists, experts in biotechnologies, and ethicists from around the world are currently meeting to discuss the ethics and issues surrounding de-extinction Check out the TED Talk if you’d like: extinction_are_you_ready.html

Hormones that affect Blood Sugar Representing the PANCREAS y’all!

The Pancreas The pancreas contains 2 types of cells, one which produces digestive enzymes, and another which produces hormones Hormone producing cells are found in structures called ‘islets of Langerhans’ Islets contain alpha and beta cells which produce the hormones insulin and glucagon

Hormones that affect blood sugar Insulin Discovered by Canadian scientists Banting & Best in 1921 (Banting received the Nobel Prize for this work in 1923) Produced in the beta cells of the islets of Langerhans in the pancreas Released when blood sugar levels increase (ie. after a meal) Cause the cells of muscles and the liver to become permeable to glucose In the liver, excess glucose is converted to glycogen

Hormones that affect blood sugar Glucagon Produced in the alpha islet cells Released when blood sugar level decreases Promotes conversion of glycogen to glucose There are also other secondary hormones that have an affect on blood sugar in the body

The Blood Sugar Loop: After a meal, blood sugar rises, and so insulin is released. This, in turn, leads to the uptake of glucose, lowering blood sugar When blood sugar drops, glucagon is released. This results in the conversion of glycogen to glucose and release into blood

Other Important Hormones Epinephrine & norepinephrine Also known as adrenaline & noradrenaline Produced and stored in the adrenal medulla (part of the adrenal gland above the kidney) Stress stimulates their release into the blood Result in an increased heart rate and blood sugar level Has a similar affect as the presence of glucagon

Other Important Hormones Glucocorticoids Includes cortisol Released by the anterior pituitary to help the body recover from stress Increase the level of amino acids in blood Amino acids then converted into glucose by the liver, again raising blood sugar levels

Diabetes Mellitus Chronic disease caused by insulin deficiency or “resistance” characterized by persistent hyperglycemia (blood glucose > 20 mmol/L) Symptoms: low energy, high urine volume, glucose in urine, excessive thirst, weight loss, blurred vision, acetone breath

Diabetes Mellitus There are 3 main types: Type 1: pancreas is unable to produce insulin considered a variety of autoimmune disease possible genetic component but always triggered by environmental factor(s)

Diabetes Mellitus Type 2: decreased insulin production or ineffective use of insulin by cells (“insulin resistance”, caused by defective insulin receptor on cell membrane) can be controlled with diet, exercise & drugs that stimulate the pancreas strong genetic component Type 3: gestational diabetes similar to type 2, but usually temporary

Diabetes Mellitus Treatment: frequent monitoring of blood sugar levels, close attention to carb intake (no simple sugars in diet), exercise For type 1, insulin injection by syringe, pump or pen. Possible islet cell transplant (still in experimental stages) Untreated: leads to blindness, kidney failure, nerve damage, massive cell death (necrosis and gangrene)

Lab Exercise Effects of Hormones of Blood Sugar Lab exercise – pg. 401