The document discusses the human digestive system and nutrients. It defines nutrients as substances that provide energy and materials for cell growth and repair. The main classes of nutrients are carbohydrates, proteins, fats, vitamins, minerals, and water. Enzymes help speed up chemical reactions in digestion by breaking down nutrients. The stages of digestion include the mouth, esophagus, stomach, small intestine, pancreas, large intestine, liver, gallbladder and rectum, each playing a role in breaking down food into smaller molecules that can be absorbed and used by the body.

1. Digestion Clip by Brainpop

2. Nutrients…
• Are substances in food that provide
energy and materials for cell
development, growth, and repair.

3. Classes of Nutrients
Carbohydrates: main source of energy
Proteins: used for growth. Made of
amino acids.
Fats: provide energy (stored) and help
body absorb vitamins
Vitamins: organic nutrients that help
your body to use other nutrients.

4. Classes of Nutrients
Carbohydrates
Proteins
Fats
Vitamins.
ORGANIC
(Contain carbon)

5. Classes of Nutrients
Minerals: Inorganic nutrients that
regulate many chemical reactions in
your body.
Water: Most vital factor for survival,
other than oxygen. Water enables
chemical reactions to take place in
your cells.

6. Classes of Nutrients
Minerals
Water
Digestion and
Nutrients
Inorganic
(no carbon)

7. Enzymes
 Enzymes are molecules that speed up the
rate of chemical reactions
 They do this without being changed or
used up.
 Enzymes also speed up reactions by
reducing amount of energy necessary for
a chemical change to begin.

8. Digestive Enzymes are:
AMYLASE is a starch-degrading enzyme
secreted in the mouth. This enzyme
breaks down carbohydrates.
PEPSIN, found in the stomach, causes
complex proteins to break down into less
complex proteins.
Enzymes are also responsible for MANY
chemical reactions in your body---not just
the ones involved in digestion!

10. Your Digestive System
Mouth: Begins chemical & mechanical
digestion, glands in mouth produce
saliva, which contains amylase, which
breaks down starch
MOUT
H

11. Your Digestive System
Esophagus: muscular tube that
connects throat to stomach. Moves
food down by squeezing (peristalsis)
ESOPHAGU
S

12. Your Digestive System
Stomach: muscular bag where chemical
and mechanical digestion continue;
food stays here ~4 hours, changes to
chyme
STOMACH

13. Your Digestive System
Small Intestine: tube nearly 7 meters long
where digestive juices from liver and
pancreas are added; villi absorb molecules
from chyme
Small Intestine

14. Your Digestive System
Pancreas: a small organ that produces
substances that stop the action of
stomach acid, makes enzymes that
break down carbohydrates
PANCREAS

15. Your Digestive System
Large Intestine: absorbs water from
undigested food, where unabsorbed
materials become more solid
LARGE
INTESTINE

16. Your Digestive System
Liver: produces bile, which is stored in
gall bladder. Bile breaks up large
particles of fats into smaller
particles.
LIVER

17. Your Digestive System
Gall Bladder: small sac that stores bile
produced by liver
GALL BLADDER

18. Your Digestive System
Rectum: where muscles control the
release of wastes from the body
RECTUM

19. Digestive System Clip by Brainpop
The Process of Digestion Clip
(13 minutes)