Osmoregulation and Excretion 22 April 20151Osmoregulation.ppt.
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Transcript of Osmoregulation and Excretion 22 April 20151Osmoregulation.ppt.
Animal Life
22 April 2015 Osmoregulation.ppt 2
• Multicellular organisms• Internal circulation
• Coordination, information transfer
• Structural maintenance
• Movement
• Maintenance of homeostatic internal environment• Excretion of N waste
• Regulation of pH
22 April 2015 Osmoregulation.ppt 3
How neurons conduct impulses:• Membrane potential (in
neurons, muscle cells, etc.)
• K+ diffuses out, Na+ diffuses in,
• Na-K pump moves Na+ out & K+ in.
• Cl-, phosphate, protein anions balance cations
• “Resting potential” = - 70 mV
Imbalance of electrolytes results in serious disorders
22 April 2015 Osmoregulation.ppt 4
Osmoregulation
• Maintaining osmotic homeostasis• Balancing water and
electrolyte concentrations
• Maintains cell integrity
• Maintains enzyme function
• etc.
22 April 2015 Osmoregulation.ppt 5
Osmosis
• Diffusion of water from high water concentration to lower water concentration.• Water loss
• Water gain
22 April 2015 Osmoregulation.ppt 6
Osmosis Marine fish lose water by osmosis• Actively excrete salt to maintain homeostasis
Freshwater fish gain water by osmosis • Excrete excess water
Nitrogenous wastes
22 April 2015 Osmoregulation.ppt 7
• Produced from metabolism of amino acids and nucleic acids• Ammonia
• Urea
• Uric acid
• Guanine• Arachnids
Nitrogenous wastes
22 April 2015 Osmoregulation.ppt 8
• Produced from metabolism of amino acids and nucleic acids• Uric acid from birds
Nitrogenous waste & Osmoregulation
• Same systems balance water and dispose of nitrogenous wastes • Protonephridia & “flame
bulbs” in flatworms
• Metanephridia in annelids
• Malpighian tubules in arthropods
22 April 2015 Osmoregulation.ppt 9
Humans
• Body Water• 75% of body weight in infant• 60% of body weight in adult male • 55% of body weight in adult female– Reasons for differences ??
22 April 2015 Osmoregulation.ppt 10
22 April 2015 Osmoregulation.ppt 11
Osmoregulation
• Fluid compartments”• Intracellular fluid
• Extracellular fluid• Interstitial (tissue)
fluid
• Blood plasma
• Lymph
Osmoregulation
• Exchanges among compartments• Intracellular – interstitial• Diffusion, facilitated diffusion, osmosis, active
transport
• Interstitial fluid (excess) lymph • Lymph blood plasma• Plasma interstitial fluid
• Filtration from capillaries carries electrolytes & nutrients to cells
22 April 2015 Osmoregulation.ppt 12
Osmoregulation
22 April 2015 Osmoregulation.ppt 13
• Regulation of blood plasma regulates all body fluids
• Parts of osmoregulation• Filtration
• Reabsorption
• Secretion
• Excretion (disposal)
Kidney
22 April 2015 Osmoregulation.ppt 14
• NephronRenal corpuscle
• Glomerulus
• Bowman’s capsule
Tubule• Proximal convoluted
tubule
• Loop of Henle
• Distal convoluted tubule
Nephron
• Filtration in renal corpuscle • Afferent arteriole
• Glomerular capillaries
• Podocytes of Bowman’s capsule
• Efferent arteriole
22 April 2015 Osmoregulation.ppt 15
Osmoregulation
• Reabsorption in proximal convoluted tubule • Active transport of Na+
• Co-transport of glucose, amino acids, etc.
• Cl- follows Na+
• Osmosis of water
• Diffusion of non-polar molecules
• Diffusion of urea
22 April 2015 Osmoregulation.ppt 16
Osmoregulation
22 April 2015 Osmoregulation.ppt 17
• Loop of Henle • Concentration of
salts in medulla of kidney
Osmoregulation
22 April 2015 Osmoregulation.ppt 18
• Reabsorption and tubular secretion in distal convoluted tubule• Recovery of NaCl,
water,
• Reabsorption of HCO3-
• Secretion of H+, K+
• pH regulation • Sources of metabolic H+
Osmoregulation
22 April 2015 Osmoregulation.ppt 19
• Collecting duct• Filtrate/urine makes
one more pass through medulla• Final reabsorption
(or not)
Osmoregulation
• Antidiuretic hormone (ADH) • Causes recovery of water
• Absence excretion of water
• Important for water homeostasis
22 April 2015 Osmoregulation.ppt 20
OsmoregulationDiuretics
• Ethyl alcohol– Beer, wine, liquor
– Inhibits ADH release• Water NOT recovered
• Caffeine– Coffee, tea, Coke, etc.
– Inhibits Na+ transport• Sodium, water, etc.
NOT recovered
22 April 2015 Osmoregulation.ppt 21
Urine Drainage
• Collecting ducts to • Minor calyx• Major calyx• Renal pelvis• Ureter
22 April 2015 Osmoregulation.ppt 22
Urine Drainage
• Ureter to Urinary bladder
• Detrusor muscle• Smooth muscle of
bladder
• Urethra• internal sphincter
• external sphincter
22 April 2015 Osmoregulation.ppt 23