Biology 202

  1. integumentary system
    • functions in: protection, communication, respiration, excretion, osmoregulation
    • includes two main multicellular layers: the epidermis (derivedfrom the ectoderm, originally alive) and the dermis (frommesoderm)
    • also, blood vessels, nerves andmucous gland
  2. lecture additions:
    • largest organ system of the body
    • specialized in fish and mamals (fur/scales)
    • functions in immune system
    • and portrays emotion (blushing)
    • osmoregulation helsp with salt regulation and retention
    • in most (non land) vertebrates the skin is alive and active
    • dermis contains fibro blasts (secrete collogen) blood vessels nerves and mucous glands (maintains moist skin and helps with kldfs)
  3. skeletal system
    • functions in support, protection and movement
    • originally made of cartilage, and included only the gillsupports & axial skeleton (notochord, cranium & vertebrae)
    • bone appeared early in vertebrate evolution:
    • endochondral (laid downwithin cartilage)
    • dermal (laid down by thedermis)
  4. lecture additions
    • diagram is a lamprey (good judge of what original vertebreys look like)
    • all vertebrates have a cranium and vertebrae
    • bones help store calcium (rare occuring in environment)
    • Osteocytes take up and lay down calcium
    • original vertebrates didnt have jaws or paired appendages
  5. muscular system
    • functions in support and movement
    • includes three muscle types
    • smooth (involuntary; usually visceral)
    • striated (skeletal; usually somatic) - originally arranged in 'W' shaped myomeres
    • cardiac (heart)
  6. lecture additions
    • smooth muscle only his 1 nucleus/ usually only occurs in organs (the viscera), have longer and stronger contractions that skeletal muscle
    • striated also called skeletal, somatic means that its in the body limbs
    • fish fillets show the W or striated shape of skeletal muscle when cooked
    • cardiace a mix of smooth and striated, looks striated and is multi nucleate, but is also laid down in layers, and the layers are interconnected allowing the contraction of the heart as such
  7. digestive system
    • functions to release nutrientsfrom food, process and store nutrients, and neutralize toxins
    • originally, included only the mouth (inc. tongue), pharynx,esophagus, stomach, liver, pancreatic cells, small intestine and cloaca
    • intestinal lining is folded Villiinto villi and microvilli
  8. lecture additions
    • did she say less important??
    • important as many plants have toxins to pretect them selves so we need to break them down
    • mouth holds the food
    • pharynx provaides passage of food through body
    • esophogus
    • the villi and micro villi help increase the surface area which helps increase diffuseing rates
    • food is moved through system via peristalsis (anti peristalsis is the reverse movement of food through the body)
  9. respiratory system
    • functions to exchange O2, CO2, heat, salts, and N wastes
    • primitively, involved the skin plus vascularized foldings of the pharynx with muscles for pumping water
  10. lecture additions
    original vertebrates lack lungs gill coverings
  11. circulatory system
    • transports oxygen, nutrients, wastes, hormones, antibodies & heat
    • is a closed, originally single circuit
    • originally, the heart had four ‘chambers’ (contra Miller &Harley), but only one atrium and one ventricle
    • the lymphatic system recovers fluidand nutrients lost from the capillaries
  12. lecture additions
    • started out as a singles circuit (land verts developed a second one)
    • goes from gills to head to liver then to the gut then to the trunk and then the kidney (no real order other then starting at the gills)
    • 4 chambes= the conus arteriosus (prevents back flow and allows even flow rather then pumped flow), the ventricle, the atrium, and the sinus venosus
  13. excretory system
    • functions in osmoregulation and elimination of metabolic (nitrogenous) wastes
    • the functional unit ofthe kidney is thenephron - a tubulelined with specializedcells for filtering wastes from blood
    • the kidney develops sequentially from the somites
    • originally, the pronephros served inthe embryo, and the opisthonephros in the adult
    • nitrogenous waste wasprobably originally eliminated as ammonia (highly soluble, cheap toproduce)
  14. lecture additions
    • originally included the kidneys, skin, gills, & intestine
    • MISSING: no bladder
  15. reproductive system
    • functions in production and release of gametes, and maysupport developing embryos
    • gonads are multicellular (female = ovaries; male = testes)
    • ancestrally, gametes were released into the coelom, then through pores near the cloaca
    • fertilization and development were originally external
  16. lecture additions
    • lololol to the PORN OF BOX FISHIES :D
    • sperm ducts oviducts and sperm organs like the penis were not in original vertebrates
Card Set
Biology 202
lecture 2