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The big picture
Animal nutrition
Autotrophy vs.
heterotrophy
Why do we need
food?
Carbs
Proteins
Fats
Time to eat
Fig. 40.18
Essential nutrients
Malnourished vs. undernourished
What’s essential?
Stuff that ….
Amino acids
 Vitamins
 Minerals
 Fatty acids


Vitamins
__________ molecules required in very small
amounts; 13 are essential
Solubility influences over dosage concerns
Essential amino acids
Humans cannot synthesize 8 of the 20 AA’s needed
to make proteins; also difficult to store
Can lead to protein deficiency, especially in infants
Some obvious sources of AA’s?
 Also…
Minerals
_______ nutrients required in small amounts
Bighorn sheep
Fig. 41.3
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Feeding categories
What they eat
Herbivores
Carnivores
Omnivores
Are these strict categories?
Feeding mechanisms
How they eat
Suspension feeders
Substrate feeders
Fluid feeders
Bulk feeders
Fig. 41.6
Food processing overview
4 stages
Ingestion adaptations
Diet vs. dentition
Red-bellied
black snake fang
Fig. 41.5
Fig. 41.16
Digesting food instead of yourself
Use specialized compartments
Intracellular digestion
Extracellular digestion
Food breakdown in compartments that are continuous with
the outside of the body
Complete digestive tracts or alimentary canals
Unidirectional; specialized regions
Paramecium
Fig. 28.17a
*
Fig. 41.8
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Down the hatch
Digestion in humans
Salivary amylase hydrolyzes starch and glycogen
Swallowing
Not swallowing
Peristalsis
Fig. 41.9
Fig. 41.10+
Digestive enzymes at work
Digestion in the stomach
Storage and
preliminary
digestion
Gastric juice
has a pH of 2
Pepsin
*
hydrolyzes
protein
*
Why not the
stomach itself?
Result: acid
chyme
Bile first
emulsifies fats
*
Commonality?
*
Fig. 41.12
Fig. 41.11
Small intestine structure
Absorption in the large intestine
Increasing surface area for what? *
*
Water recovery, bacteria (microbiome)
*
*
Fig. 41.13
Fig. 41.15
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Ruminant digestion
Digestion adaptations
Coyote
Koala
Symbiotic prokaryotes &
protists
Diet vs.
alimentary canal
Cud reentry;
Absorbs H20
Fig. 41.17
Cud digestion
Fig. 41.19
4