1. Circulatory System

2. What Do These Two Systems Have In Common? (Think-Pair-Share)
Subway System
Circulatory System

3. Job of the Circulatory System
Acts as a highway to carry oxygen and nutrients toward your cells while carrying wastes and carbon dioxide away from cells.
Your heart pumps 4300 gallons of blood per day!
THINK! - What parts make up your circulatory system?
Heart
Blood vessels (arteries, veins, capillaries)
Blood

4. The Heart
Your heart is located behind the sternum and is the size of your fist.
THINK! – What muscle tissue makes up the heart?
Cardiac
The heart has 4 chambers:
The two upper chambers are the atria.
Two lower chambers are the ventricles.
The septum is a thick muscle that separates the right and left sides of the heart so oxygen poor and oxygen rich blood do not mix.
Valves are flaps of tissue that prevent the blood from flowing backwards
Your Heart as 2 Pumps -

5. Parts of the Heart Aorta Pulmonary Artery Vena Cava Pulmonary Veins
(carries blood to body)
Pulmonary Artery
(carries blood from
the heart to the lungs)
Vena Cava
(brings blood from body
back to the heart)
Pulmonary Veins
Left Atrium
Right Atrium
Left Ventricle
Valves
Right Ventricle
Septum

6. Blood Vessels of the Body
Arteries
carry blood “away” from the heart
Veins
carry blood “back” to the heart
Capillaries
the tiniest vessels where oxygen and nutrients can diffuse from bloodstream into cells
Only 1 cell thick
You can see them nourishing the white part of your eye

7. The Heart and Circulation
The job of the heart is to circulate blood throughout the body
The Heart is really 2 pumps working side by side:
The right side pumps blood to the lungs to pick up oxygen.
The left side pumps oxygenated blood to all tissues of the body.
Check out this simple clip first

8. Activity: Trace the Pathway of Blood During a Heart Beat
1. Oxygen poor blood enters the
heart through the vena cava.
2. Blood is then pumped into the
right atrium and then right ventricle.
3. Oxygen poor blood is pumped,
exits the pulmonary artery and
goes to the lungs.
4. Once it has oxygen, blood
reenters the heart.
5. Blood is pumped into the left
atrium and then left ventricle.
6. Oxygen rich blood is pumped
out of the aorta to the body tissues.

9. Label and Color Code the Pathway of Blood
THINK! – What sound does the
heart make?
LUB DUB LUB DUB
As blood is pumped from
atria to ventricles the “lub”
sound is made
ventricles to body, the “dub”
sound is made.

10. Heart Disease Atherosclerosis Hypertension
Build up of fat and cholesterol in arteries
Leads to heart attack
Heart Disease: United Streaming
Hypertension
High blood pressure
Clogged arteries can cause high blood pressure
Normal pressure is 120/80
THINK! – What do these numbers mean?
First number – measures pressure when ventricles contract
Second number – measures pressure when ventricles relax