Exam 2

• Salt gland


  Gland that excretes salt from albatross/fish/shark so the animals can drink salt water
• Osmoregulation


  Regulation of solute concentrations and the balance of water
• Concentrations


  Relative concentrations of water and solutes must be maintained within narrow limits
• Osmosis


  Movement of water from a region of higher concentration to a region of lower concentration
• Osmolarity


  The solute concentration of a solution, determines the movement of water across a selectively permeable membrane
• Iso-osmotic


  Movement of water is equal in both directions
• Hyposmotic


  Solution with a lower concentration of solute
• Hyperosmotic


  Solution with a higher concentration of solute
• Difference in osmolarity


  Net flow of water is from the hyposmotic to the hyperosmotic solution, water will always flow to a place with more ions
• Osmoregulators


  Terrestrial animals, freshwater animals, all mammals, most amphibians, expend energy to control water uptake and loss in a hyperosmotic or hypoosmotic environment, must expend ATP to maintain osmotic gradients, actively transporting substances across membranes
• Osmoconformers


  All marine invertebrates, sharks, rays, etc., cell is ⅓ sea water, are iso-osmotic with their surroundings and do not regulate osmolarity
• Freshwater animals


  • Constantly take in water by osmosis from their hypoosmotic environment, they lose salts by diffusion and maintain water balance by excreting large amounts of dilute urine, salts lost by diffusion are replaced by foods and uptake across the gills, freshwater fish pee a lot, perch
• Marine animals


  • Constantly lose water by osmosis from their hyperosmotic environment, they gain salts by diffusion and maintain water balance by NOT peeing, cod
• Na and K


  3 Sodium (Na) in, 2 potassium (K) out
• Land animals


  • Adaptations to reduce water loss to survive on land, body coverings of most terrestrial animals help prevent dehydration, desert animals get major water savings from simple anatomical features and behaviors such as nocturnal lifestyle, maintain water balance by eating moist food and producing water metabolically through cellular respiration
• Anhydrobiosis


  Some aquatic invertebrates in temporary pods lods almost all their body water and survive in a dormant state
• Nitrogenous wastes


  Comes from metabolism of protein called catabolism, kinds of waste depends on animals evolutionary history and habitat, especially water availability, toxic to some degree which is why we need to excrete them
• Types of nitrogenous waste


  • Ammonia (most toxic, produced by aquatic animals like bony fish)
  • Urea (produced by mammals, most amphibians, sharks, and some bony fish)
  • Uric acid (produced by birds, reptiles, insects, and land snails)
• Kidneys


  • Renal artery supplies blood, renal vein sends blood out, renal cortex outer structure, renal medulla inner structure
• Nephron


  Functional unit of kidney, starts in renal cortex and ends in renal medulla
• Bowman's capsule


  • Filtration happens here, blood flows in, collects, forces filtrate into the rest of the kidney and the rest (red blood cells) goes back to the body
• Loop of Henle


  • Concentrates salt, active absorption, absorbs most remaining salts and water, fish do not have one, protect against dehydration, concentrates urine by countercurrent multiplication
• Filtering of blood


  Filtration, reabsorption, excretion
• Glomerulus


  Keep red blood cells and other big molecules from going into kidneys, sends them back to body
• Reabsorption


  • Lots of capillaries surround nephron to reabsorb sugar, salts, water
• Proximal convoluted tubule


  • Passive reabsorption, most salts, most water, all sugar reabsorbed
• Distal convoluted tubule


  • Can absorb salt, water or balance pH
• Antidiuresis


  Wall of collecting ducts are permeable to water, kidney producing concentrated urine, dehydrated
• Diuresis


  Kidney producing dilute urine, wall of collecting duct is NOT permeable to water, eater if funneled out, hydrated
• Collecting duct


  • Concentrates a final time, concentrated medullary fluid and loses water
• Reabsorption in nephrons


  Red blood cells and ions/water are sorted. Ions and water filter through glomerulus, go through proximal tubule, loop of Henle, then distal tubule, then collect duct. Red blood cells are separated from water and ions (sugar, salt), bloodstream is wrapped around tubules ready to reabsorb water.
• Pathway of reabsorption


  • Bowman's capsule
  • Proximal convoluted tubule
  • Loop of Henle
  • Distal tubule
  • Collection duct
  • Renal medulla
  • Ureter
  • Pee it out
• Herbivores


  Eat mainly plants or algae
• Carnivores


  Eat other animals
• Omnivores


  Regularly consume animals as well as plants or animals
• Diet


  Provides chemical energy which is converted into ATP, organic building blocks like carbon and nitrogen, essential nutrients that cannot be produced by the body and must be obtained from dietary sources
• Metabolism


  Sum of all biochemical activities in an organism (cell)
• Catabolism


  Breakdown of macromolecules into monomer molecules, utilizes hydrolysis
• Anabolism


  Synthesis of macromolecules from monomer molecules, utilizes dehydration synthesis
• Molecules of life


  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids