The Circulatory System
Let’s get moving on….
Your Transportation System!!
Transportation
Blood transports materials throughout the body
 Oxygen -from lungs/respiratory system to the body cells
 Nutrients -from intestines/digestive system to body cells
 Heat -waste from cellular respiration to skin/integumentary
for release
 Waste- like CO2 from cells to the lungs/respiratory system
for expulsion and toxins/urea to kidneys to be filtered out
Major Organs of the Circulatory System
Heart: cardiac muscle that pumps blood; heart
rate controlled by brain
There are four chambers in the heart:
2 upper atria (atrium) that receive blood
2 lower ventricles that pump blood
So….about how many times does your heart beat??
A minute = 60-80
An hour = 4000
A day = 100,000
A year = 37,000,000
A life time (70 years ) = 2,500,000,000
Blood vessels
• Vascular tissue: veins/arteries/capillaries-the “tubes” or vessels
through which the blood flows
• Veins- carry oxygen depleted blood TO the heart
• Arteries- carry oxygen rich blood AWAY from the heart the
all the cells in the body
• Capillaries-very thin vessels where
materials are transferred from cells into and out
of the bloodstream usually through diffusion
• There are about 60,000 miles of blood
vessels in your body…enough blood vessels
to stretch around the equator 2.5 times!!
Capillaries
• The smallest blood vessels in the body
• Links between arteries and veins
• Capillaries deliver oxygen and nutrients
(digested food) to every cell in the body and
remove the carbon dioxide and other wastes.
Blood Components
Red Blood Cell: contain a protein
hemoglobin that binds with oxygen and
carries it to cells
in the body
White Blood Cells: leukocytes- fight pathogens
(disease causing substances) in the body, different
types do different jobs, produce antibodies which are
proteins that recognize and attack specific
pathogens
Platelets: small pieces of cytoplasm that
adhere to broken blood vessels and tissues
to form a plug to stop bleeding; help clot
the blood
Plasma: liquid portion of the blood
Plasma is 90% water
The heart and lung connection…….
• Blood is pumped from the heart to the
LUNGS
___________
RED BLOOD CELLS pick
• In the lungs, the ____________________
up oxygen from the ______________(lungs)
ALVEOLI
• The OXYGENATED blood returns to the HEART.
• The oxygenated blood is pumped to the
CELLS of the body
__________
• The cells use the oxygen to carry out
________________________
CELLULAR RESPIRATION
• The waste product of cellular respiration
CARBON DIOXIDE
is _____________________
• CO2 diffuses out of the CELLS and into the
BLOODSTREAM.
The blood is pumped to the heart,
from the heart to the lungs, and from
the lungs CO2 is expelled from the
body. While in the lungs, the blood
cells pick up oxygen and start all over
again!!!
Pathway of Blood through the Heart
3. Blood is pumped
from the right
ventricle to the lungs
to drop off CO2 and
pick up oxygen
(pulmonary artery)
1. Oxygen depleted
blood from the body
enters the right
atrium (superior
and inferior vena
cava)
4. Oxygen rich blood
returns to the heart
through the left atrium
(pulmonary vein)
5. Blood flows into
the left ventricle
2. Blood flows into
the right ventricle
The Pathway of Blood Through the Heart
6. Oxygen rich blood is
pumped from the left
ventricle through the
aorta and out to the
body
Let’s keep the blood flowing…..
Valves: structures in the heart and veins that open and
close to prevent blood from flowing backwards
Heart Valves
Vein Valves
Circulatory System fun….