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chapter 44-45 - Coggle Diagram

- - - - happens when 2 solutions are separated by a membrane and have different solute concentration
      - the measurement of solute concentration is osmolarity (# of moles per liter of solution)
      - osmolarity of human blood is typically 300 milliosmoles per liter
      - water goes through semi permiable membrane from area of high solute concentration to low solute concentration
      - the solution with high solute concentration is hyperosmotic
      - the solution wit low solute concentration is hypoosmotic
      - During osmosis water flows from hypoosmotic to hyperosmotic
    - - Animals maintain osmoregulation in 2 ways osmoconformer or osmoregulator
      - all osmoconformers are marine animals because they have the same osmolarity as their environment (have a tendency to not lose or gain water)
      - Osmoregulator: controls osmularity, independent from environment
        
        in a hypoosmotic environment water wants to go into it, so it must discharge excess water
        
        in a hyper osmotic environment water wants to leave its body so it must take in water to offset water loss, or keep water in
        
        lets animals live in areas in habitable to osmoconfromers like fresh water and terrestial habitats
      - most animals cannot animals cannot tolerate major fluctuations in external fluction, these animals are called stenobaline (steno narrow, baline salt)
      - animals that can survive major external osmolarity fluctuations are called Euryhaline, barnacles and mussels (eurys broad baline salt)
      - Marine animals
        
        most marine invertebrates are osmoconformers, so no substantial challenges in water
        
        however they do transport specific solutes in levels different from the ocean, (atlantic lobsters maintain mg2+ concentrations less than concentrations of their environment)
        
        2 strategies evolved among marine animals to face challenges in a dehydrating environment
        
        1st Found in bony fishes Cods constantly eat sea water to combat the constant loss of water, and expel the excess salt through gills and kidneys
        
        2nd in Found in marine chondrorichthians (sharks,etc) they are low in salt concentration, but high in other solutes so water constantly flows into them (they dont need to drink)
        
        small influx of water in sharks is disposed of by urine produced by kidneys
      - Freshwater animals
        
        Body cells must be hyperosmotic compared to water
        
        always gain water via osmosis
        
        Solution relies on excreting large amounts of dilute urine and drinking almost no water
        
        salts lost via diffusion are replenished, via eating and taking up salt through gills
        
        Salmon have huge changes is osmoregulatory status
        
        when on rivers and streams they osmoregulate like other fresh water fishes (excreting dilute salt etc)
        
        When migrating to the ocean, salmon acclimatize.
        
        Steroid hormone cortisol increses number and size of specialized salt secrting cells
        
        this and other changes allow for salmon to live in both fresh water and ocean water. (In salt water they osmoregulate like bony fishes do. lots of salt secretion and little peeing)
      - Animals in temporary waters
        
        Extreme dehydration is fatal for most animals
        
        Some aquatic invertebrates can lose almost all their water and not die!
        
        These animals survive by going into a dormant state when habitat dries up. This adaptation is called anhydrobiosis (life without water)
        
        tartigrades/ water bears are the among the best examples
        
        less than one mm long, when active they contain 85% water by weight
        
        But they can dehydrate to less than 2% water and still survive!
        
        Dry as dust for a decades? just add water and theyll be good as new, moving and feeding
        
        Anhydrobiosis requires adaptations that keeps cell membranes intact, researchers believe that dried out individuals contain large amounts if sugar that replace the water normally associated with proteins and lipids
        
        By learning from anhydrobiosis, scientist are now able to store samples of proteins, DNA, and cells in room temperature by manufacturing materials modeled after the protectants of anhydrobiotic species
      - Land animals
        
        dehydration is a major threat for terrestrial life
        
        adaptations that reduce water loss are key to survival
        
        Waxy cuticles in plants
        
        Body coverings in terrestrial animals
        
        Waxy layes include insect exoskeletons, shells of land snails and layers of dead keratinized skin cells covering most terrestrial vertebrates
        
        many terrestrial animals are nocturnal so they don't lose a lot of water from evaporative water loss (due to low temperature, and higher humidity of night air)
        
        most terrestrial animals lose water through many routes. Urine, feces. and across skin
        
        Land animals maintain water balance by 1) drinking and eating moist foods, 2) producing water metabolically via cellular respiration
        
        Desert animals are well adapted for minimizing water loss
        
        Camels can tolerate a 7 degrees C temperature rise and not sweat, this reduces water lost in sweat
        
        they can lose 25% of their body water and survive (humans die if they even lose half of this)
    - - Maintaining osmolarity difference between an animal and its environment costs energy
        
        osmoregulators have to spend energy to maintain osmotic gradients that cause water to move in and out (use active transport to maniulate solute concentrations in their body fluids)
        
        energy cost of osmoregulation depends on difference between the animals osmolarity and its surroundings, how easily water and solutes move across animal surface and work required to pump solutes across membranes
      - Osmoregulation accounts for 5% or more of resting metabolic rate of many fishes
      - For brine shrimp, the gradient between internal and external osmolarity is large so the cost of osmoregulation is 305 of its resting metabolic rate
      - energy cost of maintaining water and salt balance in minimized by having body fluids adapted to the salinity of environment
        
        body fluids of most animals that live in fresh water have lower solute concentrations than their cousins in seawater
        
        lower osmotic difference between body fluids and environment=decrease in energy cost of osmoregulation
    - - most animals control solute concentration in cells indirectly, they manage the solute content of body fluid that bathes cells
        
        in open circulatory systems this liquid is hemolymph
        
        in closed circulatory system, fluid is interstitial fluid
        
        maintaining composition of these fluids depends on systems as small as individual cells that regulate solute movement or as big as whole organs like kidneys
        
        In most animals, osmoregulation and waste disposal relies on transport epithelia (epithelial cells specialized for moving solutes in controlled amounts in specific directions
        
        arranged in tubular networks with lots of surcae area
        
        some face outside environment directly, others line channels connected to outside by an opening
        
        some marine birds have nasal salt glands packed with transport epithelia that secrete salt, salt glands are also found in sea turtles and use active transport to secrete fluid much saltier than the ocean
  - - - Some animals excrete ammonia directly while others use urea or uric acid (different forms vary in toxicity solubility and energy cost to produce)
      - Most aquatic animals excrete ammonia
      - mammals excrete urea
      - birds and reptiles use uric acid
      - Ammonia is very toxic so its only tolerated in low concentrations
        
        animals that excrete ammonia need access to lots of water
        
        so its common in aquatic species, ammonia can easily pass through membranes and diffuse into surrounding water
        
        in invertebrates ammonia release occurs across whole body surface
      - Urea
        
        land animals do not have access to sufficient water to dilute ammonia enough to be safe to carry and excrete safely
        
        Instead vertebrates excrete a different nitrogenous waste, urea is the product of an energy consuming metabolic cycle that combines ammonia with carbon dioxide
        
        its very low toxicity and is very soluble in water, however it animals must expend energy to produce urea from ammonia (tadpoles excrete amonia when in water and excrete urea when on land and adults
      - Uric acid
        
        insects, snails, many reptiles and birds excrete uric acid
        
        its is relatively non toxic and doesnt readily dissolve in water
        
        its is secrete as paste with very little water loss
        
        uric acid is more expensive to make than urea
        
        humans and some other animals generate small amounts of uric acid, gout is a joint inflammation caused by uric acid crystals
    - - natural selection lead to the type and amount of nitrogenous waste produced by a species to be matched to its environment
      - in amphibian eggs that have no shell ammonia or urea can directly diffuse out the egg.
      - soluble wastes of mammalian embryos can be carried away by moms blood
      - for birds and reptiles however they have hard shells that let gas go through but not liquid so birds and reptiles evolved uric acid which is a harmless solid in a in the egg
      - amount produce is coupled with animals energy budget endotherms eat more food, so they produce more nitrogenous waste than ectotherms
      - Also linked to to diet, predators get most energy from protein so they excrete more nitrogen than animals that rely on lipids or carbs as energy
  - - - kidneys
        
        used by vertebrates and some chordates
        
        compact organs calle kidnets function in osmoregulation and excretion
        
        kidneys consist of tubules and are arranged in a highly organized matter ( closely associated with nearby networks of capillaries)
        
        includes duct and other structures that carry urine from the tubules to out of the kidney, and out of the body
        
        typically dont have segments but hag fish have kidneys with segemntally arranged tubules
      - Mammalian excretory system (humans)
        
        Organs
        
        kidneys
        
        ureters
        
        bladder
        
        urethra
        
        kidneys
        
        renal corex
        
        both supplied by renal artery and drained by renall vein
        
        medulla
        
        cortex and medulla have tighly packed excretory tubles and associated blood vessels
        
        excretory tubules carry and process filtrate produce by blood entering kidney
        
        nearly all fluid in filtrate is reabsorbed by surrounding blood vessels and exits kidney via renal vein
        
        remaing fluid leaves excretory ptubules as urine and is collected in renal pelvis
        
        exits kidney via ureter
        
        nephron types
        
        functional units of kidney
        
        cortical nephrons, reach only short distance into the medulla
        
        cortical neprons in the cortes
        
        juxtamedullary nephrons in the medulla
        
        glomerulus ball of capillaries where filtrate is formed
        
        bow mans capsule catch filtrate
        
        proximal tubule reabsorption of ions proteins and other important solutes
        
        loop of henle water is reabsorbed and secretion of ions
        
        disral convoluted tubule: final chance to get rif of waste
        
        collecting duct, urine collected and take out of kidney then out of body
    - - systems that perform basic excretory functions cary widely among animal groups
      - generally built as complex network of tubules (with large surface area for exchange of water and solutes)
      - proronephridia (early nephrons)
        
        proto nephridia consist of network of dead end tubules that branch throughout body
        
        beacting cilia draw water and solutes from interstitial fluid through flame bulb, releasing fitrate into tubule network
        
        filtrate moves outward through tubules and empties as urine through openings
        
        urine excreted by flat worms is low in solutes
        
        helps balance uptake of water from environment
        
        FOund in some annlids mollusc larvae and lancelers
      - metanephridia
        
        most annelids have it
        
        excretory organs collect fluid directly from coelom
        
        a pair in each section of annelid and immersed in in coelomic fluid and enveloped by capillary nerwork
        
        when cilia beat fluid is drawn into collecting tubule that includes storage bladder that opens to outside
        
        earth worms take in alot of water from the surrounding soil so their metanephridia balance the water influx by producing urine that is dilute
      - Malpighian Tubules
        
        insects and terrestrial arthropods have them
        
        extend from dead end tops immersed in hemolymph to openings in digestive tract (no filtration step)
        
        trasport epithelium secretes certain solutes, from hemolymph into lumen of the tubule water then follows solutes via osmosis
  - - - proximal tubule: reabsorption of ions along with water and valuable nutrients
      - Dexcending limp of loop of henle: reabsorption of water
      - Ascending loop henle ions are actively transported out of nephron
      - Distal tubule last chance to remove waste and contribte to pH regulation by controll secretion of H+
      - collecting duct: processes filtrate into urine and controls how concentrated urine is
    - - the mammalian kidney a=can conserve water and is a key adaptation for terrestirial mammals
      - the kidney can excrete urine 4 times more concentrated that blood and other marsupials can have urine 25times more concentrated than their blood
      - In a mammalian kidney, production of hyperosmotic urine is possible because of lots of energy on active transport
      - Loop of henle and surrounding capillaries act as a type of counter current system to generate steep osmotic gradient, also involves active transport of NaCl from filtrate
      - counter expange systems that make concentration gradients by expending energy are called counter current multiplier systems
      - te kidney for its size has some of the highest metabolic rate of any organ because lots of energy goes into maintaing the gradient
    - - vertebrates occupy diverse habitats these differences lead to variations of nephron structure and form(variations in loop of henle length and juxtamendullary nephrons and numbers of them help fine tune osmoregulation in different environments
      - mammals
        
        secrete most hyperosmotic urine
        
        dessert animals have specially high osmularity in urine by using long and many loops of henle
        
        aquatic mammals rarely have to fight dehydration and have mostly cortical nephrons (lower capacity to concentrate urine)
        
        kidney function in vampire bat
        
        as the bat feeds the bat excretes alot of dilute urine to combat getting to heavy as it needs to drink lots of blood
        
        they make extremely concentrated urine to get rid of execess nitrogen since they dont have lots of acess to water when roosting
        
        birds and other reptiles
        
        most birds live in dehydrating environments
        
        their loops of henle are less far into the medulla, so birds cant concentrate urine that highly
        
        their main water conservation method is using uric acid to get rid of nitrogen waste
        
        reptiles also may only have corticol nephrons so they use their cloaca to reabsorb water from wastes, many reptiles use uric acid which further reduces water loss
      - fresh water fishes and amphibians
        
        produce large volumes of very dlute urine
        
        kidneys packed with many cortocal nephrons and produce filtrate at high rate
        
        salt conservation relies on reabsorption of ions from filtrate in distal tubules
        
        amphibians: when n fresh water, kidneys excrete dilute urine, their skin accumulates certain salts from water by active transport, when on land water get reabsorbed by epithelium of urinary bladder
      - Marine bony fishes
        
        marine fishes hace smaller and fewer nephrons
        
        function of kidneys in marine bony fish is get rid of ions with +2 or -2 charge
        
        they get rid of the ions by secreting them into proximal tubules and excreting them in urineexcreting them in urine
        
        specialized chloride cells in gills establish ion gradients that enable secretion of excess salt into sea water
        
        generation of ion gradientts and movements of ions are crucial for salt and water balance in marine bony fishes,
  - - - Homeostatic regulation of the kidney
        
        nervous and hormonal controls manage the mammalian kidney
        
        antidiuretic hormone release from the pituitary gland to activate membrane receptors on the surface of collecting duct cells
        
        More aquaporins= more water recapture= less pee
        
        When osmularity rises, ADH is released reabsorption of water brongs blood osmularity back to set point
        
        if blood osmularity gets to low then less adh so more release of water
        
        mutations that affect ADH disrupt homeostasis by blocking insertion of aqua porins
    - - RAAS responds to drop in blood volume and preassure by increasing water and na reabsoption
      - brings back blood preassure and volume
      - triggers vasoconstriction, increases blood preassure while decreasing blood flow to capillaries
      - stimulates adrenal glands to release adesterone and causes nephrons in distal tubules and collecting duct to reabsorb Na and water to increase blood volume and preassure
      - ADH and RAAS increase water reabsorption in kidney, But ADH alone would get rid of Na too
      - RAAS helps regulate sodium and jeep it in a normal range
      - ANP opposes rAAS walls of atria in heart release ANP to increase blood pressure and volume, but inhibits the release of renin
      - ANP lowers blood pressure and volume and causes secretion of sodium ( opposite of RAAS)
      - researcher identifies neurons in the hypothalamus that you can stimulate to make an animal very thirsty or halt all water consumption immediately, even in animal is fully hydrated (or dehydrated in the case of halting water consumption)
- - - - Terminologies
        
        Types of communication path ways
        
        Endocrine: glands that excrete chemicals to the blood ie: adrenal glands
        
        Exocrine: glands that either secrete outside the body or secrete in tubes that lead out the body ie: pancreas
        
        paracrine: are chemicals that only affect nearby cells ie: interferons
        
        What type of communication signals are their
        
        neurotransmitter: chemicals that carry messeges (chemical messenger that are of the brain, CNS and nerves
        
        Hormones: chemicals found in blood: IE insulin, Glucagon, adrenaline
        
        Steroids: lipid based chemicals that travel through blood, they are non polar
        
        poly peptides: short chains of amino acids (parts of proteins) most hormones are polypeptides
        
        amines:modified amino acids that act as messeger in blood
        
        NO and ATP can act as hormones, NO levels raised= viagra
        
        Neuroendocrine: bridge the gap between endocrine and brain, the hypothalumus talks to the pituitary glands, pituitary gland is the "master gland that talks to other glands, and its boss is the hypothalumus
        
        location of target receptors
        
        water-soluble hormones dont affect the whole body think (proteins, amines and peptides
        
        lipid soluable hormones: affect the whole body
        
        hormone affects
        
        stimulation: increase metabolic activity
        
        inhibition: decrease metabolic activity
        
        agonists: increase affects of other hormones
        
        antagonists decrease affects of other hormones
        
        affects of hormone deficiency and overload
        
        down regulation: builds tolerance (cells have less receptors
        
        Up regulation: happens when there is too little hormone, receptors on cells increase
      - Glands and hormones
        
        Parathyroid
        
        location side of the thyroid
        
        Hormone: parathyroid hormone brings calcium out of bones and into blood
        
        Adrenal hlands
        
        Cortex: outer part of adrenal gland
        
        mineralocorticoids: balance sodium and ions (or minerals)
        
        Glucoocorticoids: balances sugar in blood (helps trigger sugar) avalability, (fat into blood sugar)
        
        Gonadocorticoids: produce small amounts of estrogen for men and testosterone for women
        
        Center of adrenal gland
        
        epinephrine: triggers fight or flight
        
        norepinephrine: trigger fight or flight
        
        pancreas
        
        insulin: triggers cells to uptake blood sugar
        
        glucagon: trigger cells in the liver to release glucose
        
        Gonads
        
        Estrogen: turns girls into women
        
        testosterone: turns boys into men
        
        Pineal gland
        
        Above hypothalumus
        
        produces melatonin: regulates sleeping pattern
        
        Thymus
        
        in front of your heart
        
        tproduce thymocin, triggers development of T cells
        
        Pituatary gland (front)
        
        adrenocotropic hormone: stimulates adrenal cortex glands
        
        stimulates adrenal cortex glands
        
        LH/ CSH: stimulate egg/sperm production, also stimulates release of testosterone or estrogen
        
        Prolactin: triggers lactation
        
        melanocyte: trigger melanin production
        
        Growth hormone: stimulates mitosis
        
        Thyroid stimulating hormone: stimulate thyroid to release thyroid hormone, which then makes metabolism faster
        
        posterior
        
        Oxytocin: triggers contraction and milk release
        
        ADH: anti pee hormone, makes you pee less
        
        thyroid (front of larynx)
        
        thyroid hormone: makes metabolism faster directly controls metabolid rate
        
        calcetonin: tells calcium to go from your blood and into your bones