The
Circulatory
System
Period 7
Circulatory System or Cardiovascular System
What is it?
A system responsible for the distribution of:
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Blood
Nutrients (amino acids and electrolytes)
Hormones
Oxygen
Other gases
Main Functions
Allows blood to flow through the body, carrying nutrients to and
from cells.
In addition to blood, the circulatory system moves lymph, which is a
clear fluid that helps rid the body of unwanted material.
Cardiovascular Component
• Heart
• Blood
• Blood Vessels
The heart is a muscular pump, it’s
main function is to propel blood
throughout the body.
Chambers of the Human Heart
There are 4 chambers of the Human Heart:
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Right Atrium (receives deoxygenated
blood from the body)
Right Ventricle (pumps deoxygenated
blood to the lungs)
Left Ventricle (receives oxygenated
blood from the lungs)
Left Atrium (pumps oxygenated blood
into the body)
Circulatory Pathways
Two Systems:
• Pulmonary Circuit (lungs)
• Systemic Circuit (rest of the body)
Pulmonary Circulation
• Lungs
A "loop" through the lungs where blood is oxygenated.
The pulmonary circulatory system sends oxygen depleted blood
away from the heart through the pulmonary artery to the lungs and
returns oxygenated blood to the heart through the pulmonary veins.
Pulmonary Circuit
Deoxygenated blood:
Blood that has exchanged oxygen for carbon dioxide,
contains mostly carbon dioxide
Blood enters Right
Atrium from the
rest of the body
Blood drains into
Right Ventricle
Right ventricle
contracts, forcing
deoxygenated blood
into pulmonary artery
Systemic Circulation
• Arteries
• Veins
• Coronary and Portal Vessels
Runs through the body to provide
oxygenated blood. The blood from heart
services the body's cells and then re-enters
the heart.
Components of Blood
Plasma
• Liquid component
• Consists of water, sugar, fat, proteins and salt
• Transports cells, waste, antibodies, clotting proteins, etc.
Red blood cells
• Most abundant cell in blood
• Bioconcave disk with no nucleus, allows travel through small vessels
• Carries oxygen, throughout and returns carbon dioxide
White blood cells
• Protects body from infection, one type targets infectious cells/tumors, other
type targets bacteria/viruses
Platelets
• Small fragments of cells
• Help with clotting
Arteries Vs. Veins
Carries oxygenated blood
Can handle high pressure
Red blood vessels
Carries blood away from the
heart
• Located deeper in the body
• Rigid cell walls
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• Carries deoxygenated blood
• Layered with semilunar valves
that prevent blood flow in the
opposite direction
• Blue blood vessels
• Carries blood to the heart
• Located close to the surface
• Collapsible cell walls
Blood Pressure
• The pressure of blood against blood vessel walls in the
circulatory system.
• Regulated by changes in diameter of blood vessels in response to
changes in the cardiac output and stroke volume.
o Cardiac output is the volume of blood being pumped by the
heart, in particular by a left or right ventricle in the time
interval of one minute.
o Stroke volume is the volume of blood pumped from one
ventricle of the heart with each beat.
Homeostasis
• Capillaries dilate, allowing heat from the blood to radiate off of
the skin and out of the body (counteracts heat)
○ Prevents overheating
• Your heart will beat faster and pump more blood to the cells that
need the oxygen while exercising
○ Your cells use up more oxygen during exercise so oxygen
needs to be moved through the body quicker
Disorders Related to the Circulatory System
Atherosclerosis - hardening of plaque on walls of blood vessels
causes them to become less stretchy. Causes high blood pressure,
kidney damage, heart damage, stroke. How to avoid: refrain from
eating foods high in fat.
Disorders Related to the Circulatory System
Hemophilia - deficiency in factor VIII, an essential protein for clotting
blood. Causes anemia, excessive bleeding.
Interaction with Respiratory System
The Circulatory system pumps blood into the lungs where carbon
dioxide is taken from blood cells and oxygen is imputed back in for
the cells to distribute to the body. The lungs then release the blood
cells back into the heart and rest of the body to spread oxygen.
Interaction with the Digestive System
The Digestive System breaks down food into key nutrients and other
smaller molecules. These molecules are then deposited in the
bloodstream and distributed to other areas of the body where
nutrients are needed.
Sources
http://www.webmd.com/heart/chambers-of-the-heart
http://www.livescience.com/22486-circulatory-system.html
http://www.peteducation.com/article.cfm?c=16+2160&aid=2951
http://www.dummies.com/how-to/content/the-path-of-blood-through-the-human-body.html
http://www.hematology.org/Patients/Basics/
http://kidshealth.org/en/parents/heart.html
http://cardiosystemweebly.weebly.com/maintaining-homeostasis.html
https://answers.yahoo.com/question/index?qid=20090105185827AAi8tEg
https://www.reference.com/science/circulatory-respiratory-systems-work-together-b3a3b7c7e214bb#
https://www.boundless.com/biology/textbooks/boundless-biology-textbook/the-circulatory-system40/blood-flow-and-blood-pressure-regulation-227/blood-pressure-855-12100/