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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