This is what you should have learned in high school about nutrition and digestion, from Jim Buckley, Edwards-Knox Central School, Russell, New York.  Try Mr. Buckley's quiz1 and quiz2 on human digestion for his high school students.

If you don't have your textbook, here is the Digestive System from the On-line Biology book.

DIGESTIVE SYSTEM AND NUTRITION

EVOLUTION OF NUTRITION

• autotrophs
• heterotrophs

CALORIES and ENERGY

• 1 Calorie = 1 kilocalorie = 1000 calories

MACRONUTRIENTS

• macronutrients in the diet [Fig. 37.1; Table 37.1]
1. CARBOHYDRATES: carbon and energy
   • sugars, starches, cellulose
2. LIPIDS ("Fats"): highly compact energy-storage
   • fuel, membranes, bile salts
3. PROTEINS: basic to the structure and function of cells

MICRONUTRIENTS

1. VITAMINS
   1. Fat Soluble [Fig. 37.5]: A, D, E, K
   2. Water Soluble [Table 37.4]: B group, C
2. MINERALS
   1. essential (macro) minerals [Table 37.2]
   2. trace minerals [Table 37.3]

DIGESTION

to learn more about the human digestive system, go to HUMAN ANATOMY On-Line.

1. intracellular digestion [fig 37.2a]
2. extracellular digestion [Fig. 37.2b]
3. digestive enzymes

FEEDING MECHANISMS and ANIMAL DIGESTIVE TRACTS

1. Continuous Feeders
   1. suspension (filter) feeders: [Box 37.1] [Box 37.2]
   2. deposit feeders
2. B. Discontinuous Feeders
   1. herbivores
   2. carnivores: predation
   3. insectivores
   4. omnivores
   5. fluid feeders: sanguivores and nectivores
3. digestive system: ingestion =>digestion  => absorption  => egestion
   1. Incomplete Digestive System
      1. gastrovascular cavity: cnidarians and planarians [Fig. 37.3 a, b]
   2. Complete Digestive System
      1. alimentary canal with mouth and anus [fig 37.3d]
      2. peristaltic contractions (peristalsis) [Fig. 37.13a]
      3. segmentation [Fig. 37.13b]

VERTEBRATE DIGESTIVE STRUCTURES - ORGANIZATION OF THE ALIMENTARY CANAL

• TONGUES
  1. lampreys [Fig. 37.6a]
  2. fish [Fig. 37.6b]
  3. tetrapods [Fig. 37.6c, d]
• TEETH
  1. present in most vertebrates except birds, turtles, baleen whales
  2. Mammalian herbivores, carnivores, and omnivores [Fig. 37.7b-f; 37.14]
• SALIVARY GLANDS
  1. saliva and salivary amylase
  2. venom glands in poisonous snakes
• Pharynx and Epiglottis
• ESOPHAGUS
  1. peristalsis
  2. sphincter
  3. crop [Fig. 37.8a]
• STOMACH [Fig. 37.15]:
  1. gastric glands
     1. chief cells secrete pepsinogen: in acid -> pepsin
     2. parietal cells secrete HCl
  2. mucous cells
  3. chyme
  4. pylorus
• GIZZARD
• RUMEN [Fig. 37.9]
• INTESTINE [Fig. 37.11]
  1. earthworm: typhlosole
  2. Vertebrate SMALL INTESTINE: villi [Fig. 37.16]; microvilli; and brush border.
     1. duodenum: most chemical digestion takes place here
        1. bile: from LIVER to GALL BLADDER; bile salts
        2. PANCREAS
           1. sodium bicarbonate, trypsin, pancreatic amylase, lipase
        3. membrane enzymes: maltase and peptidases
     2. jejunum and ileum: specialized for absorption
        1. villi
        2. lacteals
• CECUM
  1. vermiform appendix
  2. cellulose digestion in horses, rats and rabbits [Fig. 37.10]
  3. reprocessing after coprophagy to obtain vitamins in mice and rabbits
• LARGE INTESTINE or colon
  1. Region of Water Absorption and Concentration of Solids
  2. bacterial production of vitamin K and some B vitamins
• Rectum and Anus

FUNCTIONS OF THE LIVER

• three fundamental roles of the liver

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