nutrition

• autotrophic nutrition is where organisms make their own food from simple inorganic raw materials. examples are

  phototrophic - uses light to make food (photosynthesis)

  chemotrophic - uses energy from chemical reactions (chemosynthesis)
• heterotrophic nutrition is when organisms cant make their own food so consume complex organic molecules. examples include

  saprotrophic- feed on dead or decaying matter and digest extracellularly

  parasitic- obtaining nutrients through another living organism

  holozoic-ingest, digest, absorb, egest food until the indigestible remains
• what are the two types of parasite

  • endoparasite- lives within the organism
  • ectoparasite-lives on surface of organism
• what are the five layers on the gut wall

  1. mucosa
  2. submucosa
  3. circular muscles
  4. longitudinal muscles
  5. serosa
• an example of a endoparasite is a pork-tapeworm
• an example of an ectoparasite is human headlice
• name the main types of digestive enzymes

  • proteases
  • lipases
  • carbohydrases
• the two types of peptidases are

  1. endopeptidase- breaks peptide bonds within protein chain
  2. exopeptidase- breaks peptide bonds at the ends of chains
• what extra layer does the stomach have compared to the gut wall

  oblique muscle layer
• what is gastric juice

  secreted from gastric pits in the mucosa it contains peptidases, pepsinogen, HCl, mucus
• what cells are peptidases secreted from (gastric pits)

  chief cells
• what cells is HCl secreted from (gastric pits)

  oxyntic cells
• what cells is mucus secreted from (gastric pits)

  goblet cells
• what is the role for bile

  • neutralise stomach acid
  • emulsify lipids to increase the surface area
• adaptations for the villi

  • microvilli - increase surface area
  • capillaries -rich blood supply for conc gradient
  • lacteal - absorb lipids
  • epithelium is only once cell thick for short diffusion distance
  • epithelium cells have lots of mitochondria for ATP
• how amino acids travel to the capillaries

  facilitated diffusion
• how does glucose travel to the capillaries

  co-transport with Na then facilitated diffusion
• how does fatty acids and glycerol travel to the lacteal

  diffusion
• how do minerals travel to the capillaries

  active transport
• how does water travel to the capillaries

  osmosis
• which vitamins are water soluble

  • B
  • C
• which vitamins are lipid soluble

  • A
  • D
• dentition is the teeth and their supporting structures, including the gums and bone
• name the different types of teeth starting at the front

  1. incisors
  2. canines
  3. premolars
  4. carnassials
  5. molars
• ruminants are groups of herbivore animals that eat a lot of cellulose

  they also have four chambers in their stomach
• name the four chambers in the ruminant stomach

  1. rumen
  2. reticulum
  3. omasum
  4. abomasum
• the role of the rumen is for the food to mix with the microbes that secrete enzymes to digest cellulose
• the function of the reticulum is fermented grass is reformed into cud and regurgitated to the mouth for further chewing
• the function of the omasum is its where water and organic acids are absorbed into the blood
• the function of the abomasum is the `true` stomach where protein is digested by pepsin at ph 2
• where is amylase produced

  mouth and pancreas
• where are endopeptidases produced

  pancreas
• where are exopeptidases produced

  pancreas and small intestine
• where is lipase produced

  mouth, stomach, pancreas
• where is carbohydrase produced

  small intestine, pancreas, mouth
• what is the diastema

  gap in the teeth between premolars and incisors and carnivores

  it allows more tongue movement and allows to grasp onto the grass
• what are the adaptations of the villi

  • one cell thick
  • rich blood supply
  • lacteal
  • microvilli