digestion Flashcards
kilocalories and calories
bond energy
raise temperature of 1L of water by 1C
caloric values
(in ascending order)
proteins - must lose N; feed into glycolysis, krebs cycle, oxidative phosphorylation
CHO - production of co2
fats - feed into CHO metabolizing pathways
the Sun
ultimate energy source
photosynthesis
geothermal vents
extremely acidic
rich source of H2S
Mponeg Gold Mine
no light or heat
radioactive decay of elements supports growth of bacteria as source of energy for animals
oriental hornet
anti-reflective, light trapping bands
develops voltage gradient to drive ATP production
filter feeders
water with food is strained over gills or other structures to remove food
hematophagy
blood eaters
very efficient way to transmit infections - lyme disease, babesiosis
liquid digestion
highly specialized animals
adapted to food source
symbiotic relationship
parasites!
milk
mammalian trait
wide range of protein, fat and carbs
seawater
organic molecules at very low concentrations
uptake by active transport
very little energy per liter unless filtered
polyphyodont
teeth replaced
diphyodont
teeth not replaced
radula
invertebrates
analogous to teeth
proboscis
invertebrate elongated tube (no tongues)
protein metabolism
all animals require proteins and digest it in the same way (cannot produce all amino acids)
protein digestion requirements
high acidity
protease activity
amino acid types
acidic
basic
lipophilic
neutral
lipid metabolism
all animals need lipids and metabolize them the same way, but NOT the same lipids
lipid digestion requirements
lipases (complex –> simple)
carbohydrate metabolism
all animals have the enzymatic machinery required to digest glucose
carbohydrate digestion processes
glycolysis
citric acid cycle
ox/phos
CHOs
ideal fuel
consumes o2 and produces co2
optimized for ATP production
batch reactors
invertebrates
one entrance
digestion, absorption and waste generation in one place
plug-flow reactor
all vertebrates and many invertebrates
digestion, absorption, and waste generation in different places
continuous flow stirred tank reactors
fermentation of cellulose
ruminants and termites
invertebrates and algae
algae convert sunlight into complete carbs for invertebrates
invertebrates produce waste (NH3), used by algae for protein synthesis
prolonged survivorship during periods of starvation
microbiome
surface or internal complex collection of bacteria and fungi, usually beneficial
hindgut fermentation
fermentation in large intestine
GI tract 10-15x body length
foregut fermentation
special stomach, regurgitation
ruminant
rumen - microbial fermentation
reticulum - separation of food particles by size, fermentation
omasum - absorption
abomasum - digestion and absorption of proteins; true stomach
primary site of absorption
wall of the small intestine
highly polarized epithelium
digestive tract
specialized place to carry out chemical and enzymatic digestion
digestive tract anatomy
foregut - esophagus
midgut - stomach
hindgut - intestinal tract
digestive tract wall
single layer polarized epithelium
large surface area - villi (folds) and microvilli (cell surface)
similar secretion of saliva acid, enzymes, buffers
alimentary canal
invertebrate entrance and exit
hollow tube at both ends
specialization along canal (separates digestion, absorption)
gastrovascular cavity
invertebrate
single opening, blind-ended tubes
taste or poisons
alkaloids and glycosides
tannins - bitter astringent
metabolic rate (Mr)
consumption of energy at a specific rate
O2 mL/g/min
basal Mr
menial energy expenditure to stay alive
good way to measure metabolism
expose animals to radioactive water
loss of both 18O and 2H after 3 weeks = energy metabolism
bomb calirometer
measure total heat production
TEE
Total Energy Expenditure
energy intake - deltaBF
if you eat more than you need you gain body fat
energy storage
fat storage - animals that move
glycogen - animals that don’t move
glycogen storage
heavier than fat, better fuel in hypoxic conditions
stored with water - HEAVIER
useful for small bursts of energy during hypoxia
