endotherm: warmed by heat generated by metabolism (mammals)

ectotherm: gain most of their heat from external sources (reptiles, fish)

convection: air or liquid moves past something and takes heat away

reduces the flow of heat between body and environment (mammals and birds)

position of dragonfly's body so it can absorb/avoid heat

bioenergetics: overall flow and transformation of energy in an animal; determines nutritional needs

basal metabolic rate (BMR): min met. rate of a nongrowing endoderm that is at rest, has an empty stomach, and isn't experiencing stress

standard metabolic rate (SMR): met. rate of a fasting, nonstressed ectotherm at rest at a particular temp.

larger animals have more body mass and require more chemical energy

more activity means needs more energy and metabolic rate goes up

nutrition: food taken in, taken apart, and absorbed

meat, eggs, and cheese provide all of these in proper proportions (problems for vegans)

essential fatty acids: can be obtained from seeds, grains, veggies

too many minerals can cause health problems (ex. too much sodium causes high blood pressure)

overdose of water-soluble vitamins are peed out and not harmful

overdose of fat-soluble vitamins are stored in body fat at toxic levels (if you lose weight, these vitamins will appear all at once and can kill you)

insufficient intake of essential nutrients can cause deformities, disease, and death

malnutrition ex. protein deficiencies in vegans

body uses up stored carbs and fat, then protein (eats at your muscles)

2) digestion: food is broken down small enough for the body to absorb

3) absorption: small nutrients absorbed in small intestine

substrate feeding: animal lives in/on food source (ex. caterpillars on leaves)

fluid feeding: suck nutrients from host's fluids (ex. mosquitos)

bulk feeding: eat relatively large pieces of food (ex. python ingesting a gazelle)

food vacuoles inside cells contain enzymes that break down molecules

enables animal to eat larger pieces of food bc has specialized organs to digest instead of relying on digestion on a cellular level

ex. hydras and flatworms have this pouch to digest their food

tube can be separated into diff. compartments like in humans or can remain simple like in earthworms

allows animals to ingest food while earlier meals are still being digested

salivary glands release saliva which contains salivary amylase to break down starch and glycogen

mucus: viscous mixture of salts, water, cells to lubricate food and protects gums and teeth from acids

chyme: mixture of gastric juices and digesting food

pepsin (a protease) begins to break down the exposed peptide bonds into smaller peptides

has pH of 2 to denature proteins and kill bacteria

infection by Helicobacter pylori (bacteria) causes ulcers in stomach lining, so antibiotics cure stomach ulcers

chyme empties into small intestine about 2-6 hours after a meal

chyme from stomach gets mixed with digestive juices from pancreas, liver, and gallbladder

arrival of chyme triggers release of hormone secretin, which triggers pancreas to secrete bicarbonate (neutralizes acidity of chyme and acts as a buffer for chemical digestion in duodenum)

bile is secreted liver and stored by gallbladder until small int. needs it

then, lipase breaks down fat droplets into fatty acids and monoglicerides that are absorbed by villi and enter the small intestine's epithelial cells

inside the cells, chylomicrons are formed from fatty acids and monoglycerides (triglicerides) and covered by phospholipids, cholesterol, and proteins (water-soluble)

liver detoxifies blood before sending it to circulate around body

appendix: little projection hanging off cecum thought to have served as a reservoir for bacteria

absorbs water from digested material (what remains is feces)

takes 12-24 hours for waste to travel length of colon by peristalsis

fiber helps move waste along colon

colon bacteria produce methane and hydrogen sulfide (farts)

pancreatic trypsin, chymotrypsin, and carboxypeptidase (proteases break down polypeptides)

pancreatic nucleases: break down nucleic acids into nucleotides

disaccharidases break down disaccharides into monosaccharides

dipeptidases, carboxypeptidase, and aminopeptidase break down small polypeptides into amino acids

nucleosidases and phosphatases break down nucleosides into nitrogen bases, sugars, and phosphates