Download Circulation

Cardiovascular
System
How materials move through the body
• The heart is a large, four-chambered organ made of cardiac
muscle.
• Arteries carry oxygenated blood – blood high in oxygen and
low in wastes like CO2
• Veins carry deoxygenated blood – blood low in oxygen but
high in wastes and carbon dioxide
• All veins and arteries are smooth muscle
• The circulatory system is divided into three parts:
• Coronary circulation – circulation through the heart
• Pulmonary circulation – circulation through the lungs
• Systemic circulation – circulation throughout the rest of the body
Main Components of the
Cardiovascular System
• The heart has four chambers
• the two on the top are called atria (atrium)
• the two on the bottom are called ventricles
• The right side of the heart receives the deoxygenated blood,
and the left side of the heart pumps the oxygenated blood
back into the body.
• To help you remember…use this: The Right side Receives and
the Left side Leaves
• The heart circulates blood from the extremities of the body
into the lungs, then back through the heart and back into the
body.
The Heart Basics
Heart Structure
Superior vena cava – blood
from the upper part of the
body
Pulmonary vein –
deoxygenated blood
to the lungs
Aorta – blood to the brain
and upper extremities
Pulmonary vein deoxygenated blood
to the lungs
pulmonary artery
Pulmonary artery
- oxygenated
blood from the
lungs
Right side of
the heart
Inferior vena cava –
blood from the
lower part of the
Aorta – blood to lower
body
extremities
Left side of the
heart
• Circulation to the heart muscle itself is called coronary
circulation.
• Because the heart is constantly beating, it needs constant
nourishment and waste removal.
• When blood can’t reach all areas of the heart muscle, this
causes a heart attack.
• Heart attacks kill parts of the heart muscle and can result in
diminished physical abilities or even death.
Coronary Circulation
Image on page 65
• Pulmonary circulation refers to the circulation of blood
through the heart and into the lungs or pulmonary system.
• The blood exchanges wastes and CO2 for oxygen and
nutrients in the lungs in tiny sacs called alveoli.
• The blood moving to the lungs travels through the
pulmonary vein and into the lungs.
• The blood moving back to the heart travels through the
pulmonary artery.
Pulmonary Circulation
Image on page 66
• Oxygenated blood moves throughout the body bringing
nutrients and oxygen to the organs and tissues.
• There are three main types of vessels in the systemic
system:
• Veins – have one-way valves that allow the blood to flow
only toward the heart
• Arteries – open tubes carrying oxygenated blood
• Capillaries – very small blood vessels with very thin walls
to allow the exchange of wastes and nutrients in tissues
Systemic Circulation
Pumped
by heart
Double-Bubble Map
Type of
Circulation
Pumped
by heart
Type of
Circulation
Double-Bubble Map
Pulmonary
circulation
Pumped
by heart
Double-Bubble Map
The path
followed…
Pulmonary
circulation
From the heart
to the lungs
and back to the
heart
Pumped
by heart
What happens
…
…
Double-Bubble Map
Pulmonary
circulation
From the heart
to the lungs
and back to the
heart
Pumped
by heart
Wastes
exchanged in
the lungs
Oxygen added
Double-Bubble Map
The path
followed…
Pulmonary
Circulation
From the heart
to the lungs
and back to the
heart
Pumped
by heart
Wastes
exchanged in
the lungs
Systemic
Circulation
Oxygen added
Double-Bubble Map
…
Pulmonary
Circulation
From the heart
to the lungs
and back to the
heart
What
happens…
Pumped
by heart
Wastes
exchanged in
the lungs
From the heart
to the body
and back to the
heart
Systemic
Circulation
Oxygen added
Double-Bubble Map
Oxygen and
nutrients
provided to cells
?
From the heart
to the lungs
and back to the
heart
Wastes
removed from
cells
Pumped
by heart
Wastes
exchanged in
the lungs
From the heart
to the body
and back to the
heart
?
Oxygen added
Double-Bubble Map
• When pressure is applied to a fluid in a closed system, the pressure is
transmitted throughout the liquid in all directions…Pascal’s Principle…
• This means that the pressure put on the blood from your heart each time
it pumps is felt throughout the body on the blood in all the veins, arteries,
and capillaries.
• Your pulse is the measurement of the pressure in your arteries as your
heart beats and sends blood pushing through your circulatory system.
• A normal resting pulse is usually between 60-100 beats per minute.
• Blood pressure is measured using two numbers…the systolic and
diastolic.
• The systolic measurement is the amount of pressure exerted when the
ventricles contract and blood is pushed out of the heart. A healthy systolic
measurement is <120.
• The diastolic measurement is the amount of pressure exerted during the
resting phase of the ventricles as they fill with blood to contract again. A
healthy diastolic measurement is <80.
• As a healthy teen, your blood pressure might be measured at 110/70.
Pulse and Blood Pressure
• Atherosclerosis – a build-up of fatty deposits on arterial
walls.
• This can cause the blood vessel walls to become stiff and
inflexible, contributing to hypertension.
• Hypertension – also known as high blood pressure, places
extra strain on the heart and internal organs.
• Heart Failure – when heart valves fail to work properly
and the blood is not pumped effectively throughout the
cardiovascular system, wastes can build up in extremities
and tissues in the extremities don’t get the nutrients they
need.
Cardiovascular Disease
• Cardiovascular Disease Prevention is simple:
• Eat a diet low in saturated fats, salts, sugar, and cholesterol.
• Many of the food high in fats, salts, sugar, and cholesterol increase fat
storage.
• Get regular exercise and relaxation.
• Regular exercise strengthens your heart muscle and relaxation lowers
blood pressure allowing your heart to work effectively. Laughter is
great for blood pressure!
• Maintain a safe weight for your age.
• Being overweight makes your heart work harder than necessary to get
nutrients to all your tissues, but being underweight causes problems
because your body doesn’t have the necessary muscle and fat mass to
allow your heart to work at peak efficiency.
• Don’t smoke and avoid drug use.
• DUH! Smoking brings toxic chemicals into your lungs and into your
circulatory system, and drugs affect the way your heart and internal
organs function.
• Some drugs can cause your blood pressure to skyrocket, resulting in
broken blood vessels and internal bleeding which can lead to death.
Cardiovascular Disease Prevention
• Blood has 4 functions in the human body:
• Blood carries oxygen from the lungs to your tissues and
CO2 from the tissues to your lungs
• Blood carries waste products from your cells to your
kidneys to be removed
• Blood transports nutrients to your cells
• Cells in blood help fight infections and help heal wounds
• Blood has 4 parts:
•
•
•
•
Plasma – the liquid part of blood
Red blood cells – the oxygen-carrying cells
White blood cells – the infection-fighting cells in the blood
Platelets – the clotting agents
Blood
• Your body contains almost 5 L (1.3 Gal) of blood.
• A pregnant woman increases her blood volume to nearly double that volume.
• Plasma makes up more than half the volume of blood
•
Contains dissolved nutrients
• Blood cells have no nuclei
•
•
Red blood cells have a life span of 120 days
Red blood cells are made at a rate of 2 million to 3 million a second in the center of long
bones
• Hemoglobin- a molecule that carries oxygen and carbon dioxide, and give blood
its red color.
• White blood cells fight off bacteria and viruses
•
White blood cells can live for months
• Platelets- plate-shaped cell fragments that clot blood
•
•
A cubic millimeter of blood contains as many as 400,000 platelets!
Platelets live anywhere between five to nine days
• Blood Clotting
Blood