Download 3.4 Circulatroy System

Chapter 3 – Human Body
Lesson 4 – Circulatory System
Main Idea
Materials needed by the cells are carried in the blood which is pumped through the
body by the heart.
Vocabulary
Heart (144) – a muscular organ that is constantly pumping blood throughout the
body
Artery(144) – carries away blood mixed with oxygen from the heart
Vein (144) – takes blood cells containing carbon dioxide back to the heart
How are materials transported through your body?
Main Idea
The circulatory system is a transport system. It consists of the heart, blood
vessels, and blood.
Supporting Details
A. The circulatory system is transport system of the body
B. The system is made up of the heart, blood vessels, and heart.
C. The heart is a muscular organ that is constantly pumping blood throughout
the body.
a. The heart receives oxygen rich blood from the lungs and pumps it into
an artery for transport through blood vessels to the cells.
b. The cells take oxygen, food, and nutrients from the blood.
c. Carbon dioxide diffuses out of the cells and is carried in the blood
through the veins back to the heart.
d. The heart pumps the carbon dioxide rich blood to the lungs to become
oxygenated (releasing the CO2 and absorbing oxygen from the lungs).
D. Parts of the circulatory system
a. Heart – muscular organ that pumps blood throughout the body.
b. Artery – thick-walled blood vessel that carries blood from the heart.
c. Vein – a blood vessel that carries blood back to the heart.
d. Capillary – smallest blood vessels , it has a thin wall.
What are the parts of the heart?
Main Idea
The heart received oxygen rich blood from the lungs and pumps it to the cells. It
received carbon dioxide rich blood from the cells and pumps it to the lungs to be
oxygenated.
Supporting Details
A. The heart is a strong muscular organ that constantly pumps blood
throughout the body.
a. It is a the size of a fist
b. It is located in the corner of the chest behind the sternum bone.
c. It has a protective sac of tissue called the pericardium surrounding it.
B. The heart has two sides separated by a muscular wall.
a. Each side the heart has an upper and lower chamber.
i. The upper chamber is the atrium; it receives the blood.
ii. The lower chamber is the ventricle; it pumps out the blood.
b. The heart has valves separating each chamber to prevent blood from
flowing in the wrong direction.
C. Right side of the heart
a. The right atrium receives carbon dioxide rich blood from 2 large veins:
the superior vena and the inferior vena.
i. The superior vena brings blood from the upper part of the body
and head to the heart.
ii. The inferior vena brings blood from the lower part of the body.
b. The blood flows from the right atrium to the right ventricle.
c. The heart pumps the CO2 rich blood out of the right ventricle into the
pulmonary artery for transport to the lungs.
D. Left side of the heart.
a. The left side of the heart receives oxygen rich blood from the
pulmonary artery coming from the lungs.
b. The blood flows into the left ventricle.
c. The blood is pumped out of the left ventricle and flows into the aorta
(a large artery ) for transport to the rest of the body.
How do blood and blood vessels work?
Main Idea
Blood is made up of red blood cells, plasma, white blood cells, and platelets.
Supporting Details
A. Blood is a liquid tissue that contains plasma, red blood cells, white blood
cells, and platelets.
a. Plasma
i. Plasma is a clear liquid that makes up about 56% of the blood.
ii. The other parts of the blood are suspended in the plasma.
iii. Plasma consists of water and proteins.
iv. Plasma transports the nutrients and vitamins from the digested
food.
b. Red blood cells
i. Red blood cells make up about 40% of the blood.
ii. Red blood cells transport oxygen that is needed for cellular
respiration in the cells.
iii. Red blood cells also transport carbon dioxide from the cells to
the lungs.
c. White blood cells
i. White blood cells and platelets make up around 4% of the
blood.
ii. White blood cells fight off any germs that enter the body.
iii. White blood cells breakdown dead cells.
iv. They are larger than red blood cells.
d. Platelets
i. Platelets are tiny cell fragments.
ii. They help the body fix itself after an injury.
iii. They clump or stick together to form a clot or a scab to stop the
bleeding in a cut.
iv. Platelets also prevent blood from leaking through broken blood
vessels. The repair the blood vessels by sticking to the broken
spots.
B. Blood is transported throughout the body through arteries, veins, and
capillaries.
a. Arteries and veins have three layers in their muscular walls.
b. The walls of veins are thinner to prevent nutrients and gases from
passing through.
c. Like the heart, some veins in your arms and legs have valves to
prevent blood from flowing in the wrong direction. The valves close to
stop blood from backing up.
d. Capillaries are tiny blood vessels that connect the arteries and veins.
i. The gas exchange in cells occur in the capillaries
ii. The capillaries have thin walls to enable:
1. Oxygen to flow from the alveoli through the walls of the
capillaries into the red blood cells
2. Oxygen to flow out of the red blood cells into the cells
3. Carbon dioxide to flow out of the cell into the red blood
cells
4. Carbon dioxide to flow out of the red blood cells and into
the lungs through the thin walls of the capillaries and
alveoli.
How do the circulatory and the respiratory systems work together?
Main Idea
The circulatory and respiratory systems work together to transport oxygen to the
cells and carbon dioxide from the cells.
Supporting Details
A. Carbon dioxide rich blood from the superior vena cava and the inferior vena
cava enters the right atrium. It flows into the right ventricle and is pumped
out through the pulmonary artery.
B. The carbon dioxide rich blood flows through the pulmonary artery into the
lungs.
C. In the lungs, the blood drops off carbon dioxide and picks up oxygen.
D. Oxygen rich blood from the lungs flows into the left atrium through the
pulmonary veins. It moves into the left ventricle where it is pumped out
through the aorta for transport to the rest of the body.