1. Ch 39 Nutrition, Digestion and absoption
AP lecture

2. Recap
Heterotrophic
Autotrophic
Catabolism
Glycogen

3. What do animals need to live?
Animals make energy using:
food
oxygen
Animals build bodies using:
food for raw materials
amino acids, sugars, fats, nucleotides
ATP energy for synthesis
food
ATP O2

4. Teeth Carnivore Herbivore Omnivore sharp ripping teeth “canines”
wide grinding teeth
molars
Omnivore
both kinds of teeth

5. Essential nutrients
Can not be synthesized in the body but are absolutely required
Macronutrients
Required in large amounts
Micronutrients
Required in small amounts
*amino acids*

6. Essential minerals Chemical element required in the diet
Calcium (macronutrient), Iron (micronutrient), and potassium

7. Essential Vitamins Carbon compounds Water soluble Fat soluble
Eliminated in the urine
Fat soluble
Build up in the body fat and become toxic to the liver
Vitamin D
Helps absorb calcium

8. Nutrient Deficiencies
Malnutrition
Lack of essential nutrients in the diet
Can lead to diseases and organ failure

9. Digestive System
Function: break down large molecules into smaller, absorbable molecules
*monomers and hydrolysis*
Tubular gut, two openings- one at each end

10. Digestive systems
Everybody’s got one!

11. Length of digestive system
Carnivores
short digestive system
protein easier to digest than cellulose
Herbivores & omnivores
long digestive system
more time to digest cellulose
symbiotic bacteria in gut

12. Overview of food flow Mouth Pharynx Esophagus Stomach Small intestine
Large intestine
Rectum

14. Mouth Digestion starts Chewing and amylase- starch digesting enzyme
Bolus- ball of food
Swallowing is an autonomic reflex
Sphincter at the base of the esophagus
Epiglottis covers the trachea to make sure food does not pass into the windpipe

16. Stomach Holds and breaks up food Starts protein digestion
Pepsinogen is inactive so it will not harm the stomach tissue lining
Pepsin is activated by HCl secreted by the stomach
Helps with digestion

17. Stomach pH is around 1
Can cause ulcers
Chyme- partly digested food, acid and enzymes
Smooth muscle pushed chyme into the small intestines through a pyloric sphincter

18. mouth
break up food
moisten food
digest starch
kill germs
stomach
kills germs
store food
break up food
digest proteins
cardiac sphincter
pyloric sphincter

19. Small intestine Digestion of carbohydrates and proteins continues
Digestion of fat
Absorbs nutrients
Duodenum – most digestion
Jejunum- absorb
Ileum – absorb

20. * Accessory organs* Liver – makes and secretes bile which is then stored in the gall bladder (then to duodenum) blood from the stomach goes to the liver to be filtered of toxins and to build macromolecules Pancreas – endocrine and exocrine gland digestive juices, glucagon and insulin

21. mouth
break up food
moisten food
digest starch
kill germs
stomach
kills germs
break up food
digest proteins
store food
liver
produces bile
- stored in gall bladder
break up fats
small intestines
breakdown all foods
- proteins
- starch
- fats
- nucleic acids
absorb nutrients
pancreas
produces enzymes to
digest proteins & starch

22. Large intestine (a.k.a) colon
Absorbs water and builds feces
*dehydration from diarrhea*