Lesson 1

Introduction to Body Systems (Machalina song)

Nutrition

Let’s figure out how many body

systems there are!

Draw in each

body part as it

is mentioned in

the song!!!

Draw a hollow

body diagram

Chorus:

Machalina Machalina

Rubenstein Walk-A-Dine

Hokey Pokey Loca

Was her name!

Brain!

Blood Vessels!

Bones!

Stomach!

Lungs!

Ovaries!

Nerves!

Thyroid!

Intestines!

Heart!

Liver!

Kidneys!

Organize the Body Systems

Which body system will help us to

perform the life process of nutrition?

The DIGESTIVE

system!

Heterotrophic Nutrition

What is it??

Heterotrophic Nutrition

• Unlike autotrophic nutrition (ex.

Photosynthesis), heterotrophs

must obtain their nutrients from

other sources by eating/absorbing!

• In humans, this involves 3

processes:

– Ingestion- consuming food

– Digestion- breaking food down

– Egestion – releasing food waste

(not excretion, not cellular waste)

What helps ALL body systems work?

Proper Nutrition!

OLD WAY NEW WAY!

6 Nutrients Found in Food

Carbohydrates

Lipids

Proteins

Vitamins

Minerals

Water

Must be

DIGESTED to

be absorbed

Absorbed

without

digestion

ORGANIC

INORGANIC

Carbohydrates Fats Proteins Vitamins Minerals

Sugar Starch

Fatty

acids glycerol

Amino

acids

Lesson 2

Mechanical vs Chemical digestion

Mouth Stomach

Dr. William Beaumont: The First GI Guy In 1822, a French-Canadian fur trader named Alexis St. Martin

was severely wounded. A shotgun blast tore open his abdominal wall

and the stomach itself. The wound was as large as the palm of a

man’s hand!

Dr. Beaumont treated the wound, but he was repeatedly

unsuccessful in fully closing the hole in St. Martin's stomach. For a

while, the hole had to be covered with cotton to prevent food and drink

from coming out! The hole in St. Martin's side was a permanent open

gastric fistula, an opening about the size of a quarter, large enough

that Beaumont could insert his entire forefinger into the stomach cavity!

This opening provided Beaumont with a unique opportunity to

study digestive processes by looking right into St. Martin’s stomach

through the hole. Beaumont removed samples of gastric juice from St.

Martin’s stomach and soaked different foods with the juice. He saw

that some foods were changed by the juice and others were not. He

even dipped food samples attached to a string directly into the open

hole of St. Martin’s stomach and watched as they were digested!

Question:

Dr. Beaumont noticed that the foods he

dropped directly into Alexis St. Martin’s

stomach took an unusually long time to be

digested. Why? What steps in the digestive

process were missing?

Dr. William Beaumont: The First GI Guy

Chewing the food with the teeth

in the mouth

Human Digestive System

Main Function

• to break down food into smaller particles

that can be absorbed and distributed for

use by all body cells

2 Types of Digestion…

1. Mechanical digestion

– chewing, tearing of food by teeth (mastication),

pushing of food by tongue

– churning by muscles of the stomach & intestines

2 Types of Digestion…

2. Chemical digestion

– Enzymes and acids break down and change

the molecules so they are able to pass into the

blood and body’s cells for use

oral cavity

esophagus

stomach

small

intestine

Large intestine or colon

rectum

salivary glands

liver

gall bladder pancreas

* are accessory

organs (help

digestion but

food does not

enter)

# 1 – 6 is the

path food

travels

Major Anatomy & Physiology of the

Human Digestive System

• Uvula – “punching bag” shaped

structure that blocks food from

entering the nasal cavity

1. Mouth (oral

cavity)

• Site of ingestion

• Digestion begins

– Contains salivary

glands that make

enzyme salivary

amylase to start

the digestion of

carbohydrates • Gleek Video

2. Esophagus (opening located in pharynx / throat)

• Food tube connecting the mouth to the

stomach

• Peristalsis – muscular contractions that push

swallowed food (a bolus) along the digestive

tract

• Epiglottis - flap that

closes over the

trachea when food

is swallowed to

prevent choking Epiglottis animation - YouTube

3. Stomach

• Muscular pouch that churns and mixes

swallowed food with gastric juices, forming

mixture called chyme

• hydrochloric acid and pepsin begin

protein digestion

• mucus lining

protects

stomach

from its own

juices

Lesson 3

Small Intestine (with villi)

and Accessory Organs

Mechanical Digestion Chemical Digestion

Tearing, grinding,

mashing of food

Uses enzymes

and acids

Ex. Mouth: teeth, tongue

Ex. Stomach: muscular

walls churning & mixing

Breaks food into

smaller pieces w/

more surface area Ex. Mouth:

starch sugars

Ex. Stomach:

proteins amino acids

Occur in

mouth &

stomach

break

down

food to be

absorbed

Changes food molecules

into building blocks

? ?

How long is the human digestive

system?

Up to 30 feet long in adults!

4. Small Intestine (narrow but long)

• most chemical digestion takes place here

(in the duodenum)

• Function is also to absorb nutrients into

bloodstream for delivery to body cells

• Villi

– finger-like projections on inside lining

– increase the surface area for nutrient absorption

– contain capillaries that absorb amino acids and

sugar

– contain lacteals (tiny lymph vessels) that absorb

fats

Villi

Label your Villus diagram

Capillary

Lacteal

Vein

Artery

Lymph

vessel

Epithelium of

small intestine

(only 1 cell thick)

Accessory Organs

Pancreas

– most enzymes for

digestion are

produced here

(protease,

amylase, lipase)

– secretes (release)

them into the

duodenum (1st part

of small intestine)

Organs that secrete substances into the digestive

tract but food does NOT pass directly through them

Accessory Organs Liver

• Produces & secretes bile

which emulsifies fats

– Bile mechanically

digests large fat

globules into smaller fat

droplets

– Provides more surface

area for enzyme lipase

to perform chemical

digestion

Accessory Organs

Gall Bladder

• small pouch that

stores and

secretes bile

made by the liver

• Located under

the liver

mouth

tongue

salivary

glands

epiglottis

esophagus

liver

stomach

pancreas

colon

small intestine

appendix

rectum anus

stomach

pancreas

liver

gall

bladder

Mechanical Digestion Chemical Digestion

Tearing, grinding,

mashing of food

Using enzymes

and acids

Ex. Mouth: teeth, tongue

Ex. Stomach: muscular

walls churning & mixing

Ex. Small Intestine:

Bile from liver

emulsifies fats

Breaks food into

smaller pieces w/

more surface area Ex. Mouth:

starch sugars

Ex. Stomach:

proteins amino acids

Ex. Small Intestine:

enzymes from

pancreas digest all

types of nutrients

Occur in

mouth &

stomach

break

down

food to be

absorbed

changes food molecules

into building blocks

Lesson 4

Large Intestine

Review Packets

BrainPOP | Digestive System

5. Large Intestine / Colon (wider but shorter)

• absorption of water from feces into the body

• Contains useful E. coli bacteria that produce

vitamins

• Feces (undigested waste) is stored in the

rectum then removed out the anus (egestion)

• Appendix – dangling structure at the

beginning of the large intestine

– helps some animals (not humans) digest cellulose

(plant material) • Video: Probiotics Gut Fauna

Lesson 5

Disorders of the Digestive System

BrainPOP | Digestive System

Disorders of the Digestive

System

Healthy or Unhealthy?

1.

Unhealthy!

Gall bladder

2.

Healthy!

Stomach

lining

Healthy or Unhealthy?

3.

Unhealthy!

Stomach ulcer

Healthy or Unhealthy?

4.

Unhealthy!

Inflammation in

colon

(Crohn’s

disease)

Healthy or Unhealthy?

5.

Healthy!

Large intestine

/ colon

Healthy or Unhealthy?

Groups

• Diarrhea

• Constipation

• Gallstones

• Heartburn

• Peptic Ulcers

• Appendicitis

Appendicitis (Appendix)

• Resulting Imbalance:

– Spread of infection or death if it bursts

• Treatment

– Surgery to remove it

– Antibiotics for infection

Constipation (Large Intestine)

• Resulting Imbalance:

– Discomfort during bowel movements

• Treatment

– drink extra water

– Fruit & veggies in diet

– Stool softener (meds)

Diarrhea (Large Intestine) • Resulting Imbalance:

– dehydration

• Treatment

– Drink water to

replenish what’s

lost

– Medication

Gallstones (Gall Bladder) • Resulting Imbalance:

– Blocked duct (tube)

– Inflammation or infection / pain

• Treatment

– Surgery to remove gall bladder

Heartburn / GERD (Esophagus) • Resulting Imbalance

– Inflammation / wearing down of

esophagus

– pain

• Treatment

– Eat smaller meals

– Avoid trigger foods (spicy)

– Meds (antacids)

Ulcers (Stomach) • Resulting Imbalance:

– Bleeding, pain

– Perforation (hole in stomach)

• Treatment

– Eliminate causes (smoking, stress)

– Meds to reduce acid production