ch. 41 Flashcards
animal nutrition process
food is taken in , taken apart, and taken up
herbivores
eat mainly plants or algae
carnivores
eat other animals
omnivores
regularly consume animals as well as plants or algae
essential nutrients
required materials that an animal cannot assemble from simpler organic molecules
4 classes of essential nutrients
- essential amino acids
- essential fatty acids
- vitamins
- minerals
where are essential nutrients obtained
animal’s diet
how many amino acids do animals require
20
how many amino acids can animals synthesize from their diet
about half - essential
how do vegetarians obtain all essential amino acids
eating a varied diet of plant proteins
fatty acids purpose
membranes, signaling, storage fats
- mammals - linoleic acid
- eats seeds, grains, vegetables
vitamins
organic molecules required in the diet in very small amounts
how many vitamins are essential for humans
13
2 categories of vitamins
fat-soluble and water-soluble
minerals
simple inorganic nutrients, usually required in small amounts
malnutrition
failure to obtain adequate nutrition
effects of malnutrition
deformities, disease, and death
undernourishment
diet does not provide enough chemical energy
what happens to undernourished individuals
- use up stored fat/carbohydrates
- break down own proteins
- lose muscle mass
- suffer protein deficiency of brain
- die or suffer irreversible damage
epidemiology
study of human health and disease in populations
what are neural tube defects in babies a result of
deficiency in folic acid in pregnant mothers
ingestion
act of eating or feeding
different types of feeders
filter, substrate, fluid, bulk
filter feeders
which sift small food particles from water
substrate feeders
live in or on food source
fluid feeders
suck nutrient-rich fluid from a living host
bulk feeders
eat relatively large pieces of food
digestion
breaking food down into molecules small enough to absorb
mechanical digestion
chewing or grinding, increases surface area of food
chemical digestion
splits food into small molecules that can pass through membranes
- enzymatic hydrolysis
enzymatic hydrolysis
splits bonds in molecules with addition of water
absorption
uptake of small molecules by body cells
elimination
passage of undigested material out of the digestive system
what reduces the risk of animals digesting their own cells/tissues?
digestive compartments
intracellular digestion
- food particles engulfed by phagocytosis and pinocytosis
- food vacuoles fuse with lysosomes containing hydrolytic enzymes
what animal uses intracellular digestion
sponges
extracellular digestion
- breaks down food particles outside of cells
- occurs in compartments continuous with outside of body
- some animals have gastrovascular cavity
complete digestive tract
have both mouth and an anus
alimentary canal
digestive tube, complete digestive tract
accessory glands of digestion
salivary glands, pancreas, liver, gallbladder
what does saliva contain
mucus (water, salts, cells, glycoproteins), amylase (breaks down amylose)
what does saliva do
lubricate food
what does the tongue do
shape food into a bolus to help with swallowing
pharynx (throat)
junction that opens to both esophagus and trachea