The Digestive and Urinary
Systems
Chapter 3, Lesson 3
8th Grade Health
The Digestive System

Breaks down food into nutrients that the
body can use!

http://kidshealth.org/misc/movie/bodyba
sics/digestive_system.html
Organs of the Digestive
System

Esophagus:
– Tube which moves swallowed food from the mouth
to the stomach.

Stomach:
– Where the food is processed. Food is mixed with
acids and enzymes to break it into tiny pieces.

Small Intestine:
– Nutrients and water are absorbed from the food
here through the Villi

Villi- tiny fingerlike structures that absorb water and
nutrients and deliver to the bloodstream.
– Small intestine is not actually small. It is around
22 feet in length!
Organs of the Digestive
System

Liver:
– Large gland that produces bile, a substance the
helps in the digestion of fats.

Gallbladder:
– Organ that stores bile until it is released in the
small intestine.

Pancreas:
– A gland that produces digestive enzymes and
chemicals that control blood sugar levels.
Organs of the Digestive
System

Large Intestine:
– Undigested materials from the small
intestine enter here. The large intestine
prepares this material to leave the body.
– Another name for the large intestine is the
colon.

After the material travels through the
large intestine, it will leave the body as
solid waste.
The Digestive System
Locate the following
structures:
•Esophagus
•Stomach
•Liver
•Small Intestine
•Large Intestine
•Gallbladder
•Pancreas
Picture from:
http://eatwellgetwell.files.wordpress.com/2006/05/digestion_goo
d2.jpg
How does digestion work?

See how food
moves through our
body!
– http://player.discover
yeducation.com/inde
x.cfm?guidAssetId=9
7D62D38-F86A45F4-9B1FFC826B77F807&bln
FromSearch=1&prod
uctcode=US
The Urinary System
Removes liquid wastes.
 Organs work together to filter wastes
from the blood and then to remove
wastes from the body.
 Eliminates waste in the form of Urine.

– Urine: pale yellow liquid composed of
water, salts, and other waste substances.
Organs of the Urinary System

Kidney:
– Organ that filters water and dissolved
wastes from the blood
– Helps maintain proper levels of water and
salt in the body.
– Produces urine.

Ureter:
– Narrow tube that connects the kidney to
the bladder.
Organs of the Urinary System

Ureter Cont’d:
– Muscles continuously squeeze and relax to keep
the urine moving.

Bladder:
– Holding tank for urine.
– As the bladder fills, it expands.
– A normal bladder can hold about 2 cups of urine.
– When it’s full, receptors produce the urge to
urinate.
Organs of the Urinary System

Urethra:
–
The tube that allows urine to pass out of
the body from the urinary bladder.
Questions:
1. How is water waste eliminated from
the body?
2. How do the kidneys protect our body?
Urinary System

Identify the
Following:
–
–
–
–

Kidneys
Ureter
Urethra
Bladder
Picture from:
http://academic.kellogg.cc.mi.us/her
brandsonc/bio201_McKinley/f271al_urinary_system__c.jpg
How do our Kidneys work?
The parts of our kidneys that work as
filters are called “nephrons.”
 Each kidney has over 1 million
nephrons.
 All of the water in the body (about 5
quarts) is filtered through the kidneys
every 45 minutes.

– Your body filters 160 quarts of water a day!
Taking Care of our Digestive
and Urinary Systems
1.
Drink Plenty of Water

2.
Maintain healthful blood pressure.

3.
Your body needs 6-8 glasses of water a day to
keep your kidneys functioning the right way!
High blood pressure can damage your kidneys.
Eat slowly.

When you eat slowly, you ensure easy
swallowing and more efficient digestion of food.
Taking Care of our Digestive
and Urinary Systems
4.
Eat plenty of dietary fiber.
 Why?



Ensure regular bowel movements
Prevent chronic constipation
Improves several conditions including heart disease
and diabetes.
 Sources:



Fruits
Vegetables
Whole Grains
Homework!

For one day, keep a record of what you
eat and drink. Analyze your record to
see if you are practicing ways to care
for your digestive and urinary systems.
– Look to see if you are drinking 6-8 glasses
of water per day and how many fiber
containing foods you eat!
Classwork – 1/15

Write two paragraphs (5 sentences
each) about what you found and how
you can improve!

Come up with a day’s worth of food that
will meet the dietary fiber and water
needs for the day!