Download Cardiovascular system

Cardiovascular system
“Cardio”= heart
“vascular”=vessels
The function of the cardiovascular system is to bring oxygen and nutrients to the cells
and take away carbon dioxide and wastes.
Three circulations of blood that occur in the cardiovascular system are:
Pulmonary circulation: Blood flows from the heart to the lungs to pick up oxygen and
drop off carbon dioxide. Then goes back to the heart.
Systemic circulation: Blood flows from the heart to the cells of the body (except for the
heart and the lungs). Oxygen is brought to the cells and carbon dioxide is picked up.
Blood goes back to the heart.
Coronary circulation: Flow of blood to the tissues of the heart.
The Heart
The beating of the heart controls the flow of blood through the body.
The picture below shows the blood through the heart and the arrows represent the
movement of blood through the heart.
Blood vessels
Arteries are blood vessels that move blood away from the heart.
Veins are blood vessels that move blood toward the heart.
Capillaries are blood vessels that connect arteries and veins. The walls are only one cell
thick which allows oxygen and nutrients to diffuse from the blood into the body’s cells.
Waste and carbon dioxide move from the body cells through the capillaries and into the
heart.
Blood pressure
Blood pressure is the force blood places on the walls of a blood vessel. Blood pressure is
highest in the arteries because the heart is forcing blood into them. It is lowest is the
veins.
Two numbers, such as 120 over 80, express blood pressure. The first number is the
measure of force on the arteries when the ventricles contract pushing the blood out of the
heart. The second number is when the ventricles relax.
Blood
Blood is made up of four parts.
Plasma- the liquid part of blood made up mostly of water. Nutrients and minerals are
dissolved in the plasma.
Red blood cells- cells that contain a protein called hemoglobin, which allows them to
carry oxygen and carbon dioxide.
White blood cells- fight bacteria, viruses, and other foreign substances.
Platelets- cell fragments that help clot blood in order to stop bleeding. They produce a
protein called fibrin which creates a sticky netting which blood cells stick to.
Blood types
There are four types of blood: A, B, AB, and O. Each type is identified based on the
protein or lack of protein it makes.
Type A blood creates protein A and it also makes an antibody against protein B
Type B blood makes protein B and makes an antibody against protein A
Type AB makes both A and B proteins and makes no antibodies.
Type O does not make either protein and make both A and B antibodies.
The antibodies prevent certain blood type from mixing.
Type A blood can only receive blood types A or O (because it makes no proteins)
Type B blood can only receive blood types B or O
Type AB –called the universal receiver because it can receive A, B, AB or O
Type O can receive only O blood but is called the universal donor because it can donate
to all blood types.
Cardiovascular Conditions
Atherosclerosis- occurs when fat builds up in the arteries. This narrows the flow of blood
through the arteries.