A polystyrene rod of length 12 in. and diameter 0.5 in. is subjectedto an 800-lb tensile load. Knowing that E 5 0.45 3 106 psi, determine(a) the elongation of the rod, (b) the normal stress in therod.
3 Stages: + Filtration: Glomerulus/Bowman’s capsule + Reabsorption: Proximal tubules (60%) + Secretion: Distal tubules Goals: Removes waste, save goodies, conserve water Nephron Diagram 1. Filtration: blood is being filtered in glomerulus, pushing GF material into Bowman’s capsule where it’s collected 2. Reabsorption: 60% of reabsorption occurs in proximal tube, Active Transport (ATP spent) to force GF material out, reabsorption occurs along entire length of tubule 3. Secretion: occurs in distal tubule, also uses Active Transport, goes into collecting duct which drains down to the renal cavity trying to conserve water ❏ Vertebrate Nephron Differences Freshwater Fish altwater Fish Environment H2O Higher Concentration ion Environment H2O Lower Concentration Body H2O Lower Concentration Body H2O Higher Concentration Constant intake of water Constant loss of water Get enough water by osmosis therefore Drinks saltwater regularly do not drink water Stores ions in tissues (urea) Large Glomerulus Small Glomerulus Short tubule: don’t want to reabsorb Long Tubule to reabsorb water water want to get rid Concentrated waste not diluted with water Diluted waste, ammonia Mammals: +Loop of Henle: constricted portion of tubule (loop) slows down Glomerular Filtrate (GF) moving through tubule Allowing for more water to be reabsorbed Allowing for more goodies to be reabsorbed Allowing more concentration secretion of wastes into tubule Wastes become 20X more concentrated +Plan of this is to minimize loss of water, goodies, and increasing concentration of waste (urea) Endocrine System Ch. 50 Fig. 50.1 Table 50.1, 50.2 Endocrine in charge of Hormonal Control of Bodily Function +Hormones: Signaling type of molecules such as Neurotransmitters (nervous system) and Pheromones Hormones are transported via blood stream and have a specific target cell Endocrine Glands are ductless secrete hormones directly into bloodstream to be distributed to body Exocrine glands have ducts such as sweat to surface of skin +Few Vertebrate endocrine glands + Associated Hormones 1. Hypothalamus/ Pituitary gland a. Hypothalamus: produce “releasing hormones” that target/regulate pituitary gland hormones FSHRH: follicle stimulation hormonereleasing hormone LHRH: luteinizing hormone releasing hormone b. Pituitary (anterior): secretes hormones that regulate other endocrine glands Gonadotropins: gonads FSH LH Thyrotropin: hormones that act on thyroid gland Adrenocorticotropic: hormones that act on adrenal gland Growth Hormones: secreted by anterior pituitary, stimulate cell division Prolactin Hormones: secreted by anterior pituitary, stimulate mammary glands to produce milk Melanophore stimulating hormone: pigment cells, react to sun c. Pituitary (posterior) Vasopressin: acts on kidney to produce urinal flow Oxytocin: stimulates release of milk of mammary glands/ stimulates muscle of uterine lining during birth 2. Metabolic Hormones + Associated Glands a. Thyroid Gland Thyroxine: promotes normal development of nervous system b. Adrenal Glands Cortisol: antiinflammatory hormone Aldosterone: promotes reabsorption in nephric tubule of kidney *Antagonist *Epinephrine: tones up body in emergency response (adrenaline) Of each other *Norepinephrine: brings body back down to normal (noradrenaline) c. Digestive Hormones Gastrin: stimulates secretion of hydrochloric acid into stomach Cholecystokinin: stimulates gallbladder to release bile salts into small intestine/ stimulates pancreas to secrete enzymatic juices into small intestine