animal nutrition i (ch. 41). keywords heterotroph autotroph herbivore carnivore omnivore...
TRANSCRIPT
Animal Nutrition I (Ch. 41)
Keywords
• Heterotroph• Autotroph• Herbivore• Carnivore• Omnivore• Intracellular digestion• Food vacuole• Extracellular digestion
• Gastrovascular cavity• Alimentary canal• Basic parts of
alimentary canal• Roles of mouth and
stomach in digestion
Some of the best known and fascinating adaptations of
animals involve their feeding and digestion
Examples:
• Reptile swallowing prey
• Baleen whales
Python
Starfish
Chiasmodon niger
Cryptopsaras couesi
Eurypharynx pelecanoides
Categories
• I. Autotroph
• II. Heterotroph– A. Herbivore– B. Carnivore– C. Omnivore
Today we’ll focus on heterotrophs:Digestion
• Basic principles
• Invertebrates
• Humans
Why is digestion necessary?
• Macromolecules cannot easily enter cell
COO-NH3+ cytoplasm
Cell membranepeptide
Small molecules such as amino acids can
cytoplasm
Cell membranePeptide being digested
cytoplasm
Cell membranePeptide being digested
cytoplasm
Cell membranePeptide being digested
cytoplasm
Cell membranePeptide being digested
cytoplasm
Cell membrane
Digested peptide
Even if macromolecules are taken in…
COO-NH3+ cytoplasm
Cell membranepeptide
Even if macromolecules are taken in…
COO-NH3+
cytoplasm
Cell membrane
peptide
They cannot be readily incorporated
COO-NH3+
cytoplasm
Cell membrane
Food peptideNew peptide
Unless broken down first
cytoplasm
Cell membrane
Food peptideNew peptide
Unless broken down first
cytoplasm
Cell membrane
Food peptideNew peptide
Unless broken down first
cytoplasm
Cell membrane
Food peptideNew peptide
This lecture will focus on how animals break down food
• I. Intracellular digestion– A. food vacuoles
• II. Extracellular digestion– A. outside organism– B. gastrovascular cavity– C. alimentary canal
I. Intracellular digestion
• A. food vacuoles
Intracellular digestion without vacuoles
Intracellular digestion without vacuoles
Intracellular digestion with vacuoles
Intracellular digestion with vacuoles
Intracellular digestion with vacuoles
Digestion in Paramecium
Intracellular digestionvs.
Extracellular digestion
Extracellular digestion
• A. outside organism
• B. gastrovascular cavities
• C. alimentary canal
Extracellular digestion
• A. outside organism
• B. gastrovascular cavities
• C. alimentary canal
Gastrovascular cavity: Hydra
Extracellular digestion
• A. outside organism
• B. gastrovascular cavities
• C. alimentary canal
Gastrovascular cavity vs. Alimentary Canal
Alimentary canal: a simple view
mouth
Mechanicaldigestion storage
absorption
anus
Basic parts of alimentary canal
Alimentary canal: mammalian
Mouth
• Mechanical
• enzymatic
Stomach
Digestive mechanisms in
stomach
• Mechanical
• Chemical
• enzymatic