1. 4 parts of digestion
1. Ingestion
2. Digestion
3. Absorbtion
4. Elimination

2. Feeding styles (adaptations)
Suspension feeders
-sift small food particles through water
Clams
oysters
baleen whales

3. Substrate-feeders
-live in or on their food
Caterpillars, worms

4. Fluid-feeders May not be parasites -hummingbirds and insects on nectar
may be parasites that live on the fluid of other organisms
-aphids (on phloem sap of plants)
-mosquitoes (on blood of mammals)
May not be parasites
-hummingbirds and insects on nectar

5. Bulk-feeders
-eat large quantity of food
-most animals

7. Digestion occurs in specialized compartments
The simplest is the gastrovascular cavity
No anus
Wastes leave via the mouth

10. Crop
-moisten & store
Gizzard
-grind
Intestine/ceca
-absorb

11. Oral cavity

12. Bulk-feeders
-eat large quantity of food
-most animals

13. Human Digestive System
True digestive structures vs. accessory structures
Mechanical digestion vs. chemical digestion

15. Digestion begins in the oral cavity:
chewing (mechanical digestion) and addition of saliva to food to form a bolus
Salivary amylase digests starch and glycogen (chemical digestion)
Antibacterial agents
pharynx

16. Involuntary contractions of smooth muscle surrounding the digestive tract propels food
Occurs in esophagus and the intestines

17. Stomach structure secrete pepsinogen. secrete HCl
HCl converts pepsinogen into pepsin
An adaptation which prevents stomach from digesting itself
Mucus cells secrete mucus
-lubricates and protects stomach

19. Helicobacter pylori

21. Including bicarbonate
Bile  emulsifies fat
Physically breaks up fat globules
Made in Liver
Stored in gall bladder
Including bicarbonate

22. Pancreatic enzymes (released into the duodenum via a duct)
Trypsin (protein digestion)
Pancreatic amylase (glycogen/starch)
Lipase (fats)
Nucleases (nucleic acids)

23. Intestinal enzymes (from wall of small intestine)
Disaccharidases (maltase, sucrase, lactase)
Dipeptidases

24. Anatomy of the small intestine

25. Villi Blood vessels LACTEAL -absorbs amino acids
-absorbs monosaccharides
-takes nutrient rich blood to liver
LACTEAL
-part of lymphatic system
-contains fluid called lymph
-collects components of fat digestion
-will eventually empty into blood vessels

26. Hepatic Portal system

27. Large
intestine
(colon)
Small
intestine
End
of small
intestine
Rectum
Anus
Unabsorbed
food material
Appendix
Cecum

28. Cecum is blind pouch at the intersection of the small and large intestines
In humans it is a vestigial organ called the ????

29. Stomach Small intestine Cecum Colon (large intestine) Carnivore
Fig a
Stomach
Small intestine
Cecum
Colon
(large
intestine)
Carnivore
Herbivore