1. Digestive System

2. Amazing Facts  We make 1-3 pints of saliva a day.
The average male will eat about 50 tons of food to sustain weight of 150 pounds
A horse’s intestines are about 89 feet long

3. How is the digestive system like a post office?

4. ANALOGY
The digestive system is like a post office it receives mail which is like the food in the digestive system, gets processed, and then is sent out.

5. FUNCTION
Converts large complex molecules (food) into simpler molecules (nutrients)
Absorbs nutrients into the bloodstream
Removes food/waste out of the body

6. What gets released when food is broken down into smaller molecules?
CELLULAR ENERGY
used for cell activities

7. Organs that work together to break down food

8. Two Types of Digestion Mechanical digestion (physical change)
Chemical digestion (chemical change)

9. Chemical or Physical change?
Mouth (teeth): chewing and grinding – PERISTALSIS
Enzymes in saliva (amylase) break down amylose (starch) into sugars
Stomach: Pepsin breaks down proteins with the help of HCl
Small intestine:
Villi absorbs nutrients
Bile (from liver) breaks down fats into smaller fat parts
Other enzymes further break down fats into fatty acids
Other enzymes further break down proteins into amino acids
Lactase breaks down lactose into glucose and galactose
Large intestine: absorbs water
Liver: Catalase breaks down H2O2 (toxin) into water and oxygen
Physical
Chemical
Chemical
Physical
Physical
Digestion take place through the interactions of enzymes, stomach acid, hormones, bile from the liver, and a network of nerves and muscles.
Chemical
Chemical
Chemical
Physical
Chemical

10. Where in the body are biomolecules digested?
Mouth
Salivary amylase breaks down starch into simple sugars-disaccharides
Esophagus
Muscles contract to push food through - PERISTALSIS
Liver
Produces bile that physically breaks down fat (lipids)
Stomach
Pepsin and HCl acid break down proteins
Small Intestine
Nutrients are absorbed into the blood (peristalsis)
Lipids  Fatty acids
Large Intestine
Removes excess water and salt

11. If you ate a meal of spaghetti and meatballs, what type of digestion would occur?
Biting and chewing
Mechanical Digestion
Amylase breaking down starch
Chemical Digestion
Pepsin breaking down proteins
Chemical Digestion
Lipids breaking down into fatty acids
Chemical Digestion

12. Chemical or Physical Change? Mechanical or Chemical Digestion?
Mouth
Chewing & Grinding
Salivary amylase breaks down starch  disaccharides (sugars)
Stomach
Smooth muscle contractions churn food
Pepsin and HCl break down proteins
Small Intestine
Muscular contractions break down and mix food with digestive enzymes like bile
Enzymes, bile finish digestion of sugars, proteins (amino acids) and lipids (fatty acids)
PHYSICAL CHANGE
CHEMICAL CHANGE
MECHANICAL DIGESTION
CHEMICAL DIGESTION

13. Why do our body systems interact with each other?
To maintain homeostasis

14. Interactions with Circulatory System
The circulatory system transports nutrients absorbed from the small intestine to all the body cells

15. In cells, nutrients are broken down into even smaller parts by lysosomes, which contain digestive enzymes

16. Interactions with Muscular System
Muscles contract to help chew and swallow food
Smooth muscles such as your stomach contracts to push food through

17. Interactions with Endocrine System
Makes the hormone insulin to regulate blood sugar

18. Interactions with Excretory System
Cells produce waste ↓ Enter the blood stream Travel to kidneys Kidneys filter the blood Turns into urine and exits

19. Interactions with Nervous System
Sends messages to digestive system when hungry, full. Signals peristalsis in digestive tract. Signals enzymes/hormones to be released.

20. Interactions with Respiratory system
Digestive system provides carbs for cellular respiration, which needs oxygen to convert it into ATP

21. Digestion of carbohydrates begins in the -
stomach
small intestine
mouth
pharynx

22. Salivary amylase breaks down _________ into _________ in the _________.
Proteins; dipeptides; stomach
Lipids; fatty acids & glycerol; small intestine
Carbohydrates; sugars; stomach
Carbohydrates; sugars; mouth

23. Proteins that catalyze biochemical reactions are?
amino acids
enzymes
substrates
chyme

24. Digestion of lipids begin in the?
mouth
small intestine
stomach
large intestine

25. Pepsin breaks down _______ in the _______?
Proteins; small intestine
Carbohydrates; mouth
Proteins; stomach
Lipids; stomach

26. Meat from a hamburger begins digestion in the?
Mouth
Stomach
Small intestine
Large intestine

27. Chemical digestion does not occur in the?
Mouth
Stomach
Small intestine
Large intestine

28. Pepsin and _______ chemically breaks down proteins in the stomach.
Trypsin
Amylase
Hydrochloric acid
Bile

29. Which of the following is an example of a chemical change?
Absorption of water from your intestine into your bloodstream
A pot of water boiling on the stove
Adding chocolate chips to batter to make chocolate chip cookie dough
Digesting a sugar cube
Dissolving cherry Kool-Aid into a glass of water

30. Which of the following is not a physical change?
Ice melting when its left out on a table
Corn being ground to make a masa for tamales
Dissolving of sugar into glass of ice tea
Peristalsis in your esophagus and small intestines
Saliva starting the breakdown of starch into sugars in your mouth