Organ SystemsOrgan Systems

The circulatory The circulatory systemsystem

What is the purpose of the What is the purpose of the circulatory system?circulatory system?

The purpose of the The purpose of the circulatory system is to:circulatory system is to: Transport nutrients and Transport nutrients and

oxygen to all the cells of oxygen to all the cells of the body.the body.

Transport wastes and Transport wastes and CO2 away from the cells CO2 away from the cells to be excreted.to be excreted.

Transport hormones.Transport hormones. Work with immune Work with immune

system to fight off system to fight off infections.infections.

What are the components of What are the components of the circulatory systemthe circulatory system

There are three There are three major components major components of the circulatory of the circulatory system.system.

1. Blood1. Blood

2. Blood vessels2. Blood vessels

3. The heart3. The heart

The BloodThe Blood

There are four major components of There are four major components of the blood. Each plays a very specific the blood. Each plays a very specific role.role.

The components are:The components are: Red Blood CellsRed Blood Cells White Blood CellsWhite Blood Cells PlateletsPlatelets PlasmaPlasma

Red Blood CellsRed Blood Cells

Red blood cells are red Red blood cells are red because they contain the because they contain the molecule Hemoglobin.molecule Hemoglobin.

Their primary responsibility Their primary responsibility is to carry oxygen to the is to carry oxygen to the cells, and carry CO2 away cells, and carry CO2 away from the cells.from the cells.

Red blood cells have no Red blood cells have no nuclei.nuclei.

Red blood cells are created Red blood cells are created in your bone marrow.in your bone marrow.

Sometimes they are Sometimes they are referred to as referred to as Erythrocytes.Erythrocytes.

White Blood CellsWhite Blood Cells

The white blood cells The white blood cells function to help your function to help your body fight off infections.body fight off infections.

There are different There are different types of white blood types of white blood cells, but they all work cells, but they all work towards the same towards the same purpose.purpose.

Sometimes white blood Sometimes white blood cells are referred to as cells are referred to as Leukocytes or Leukocytes or lymphocytes.lymphocytes.

PlasmaPlasma

Plasma is the liquid portion of your Plasma is the liquid portion of your blood, and it is made up mostly of blood, and it is made up mostly of water.water.

Dissolved nutrients and wastes are Dissolved nutrients and wastes are carried along by the plasma.carried along by the plasma.

Hormones are also trasported Hormones are also trasported through your body in the plasma.through your body in the plasma.

PlateletsPlatelets

Platelets are the smallest portion of your Platelets are the smallest portion of your blood.blood.

Platelets are responsible for repairing Platelets are responsible for repairing breaks in your blood vessels.breaks in your blood vessels.

The secrete a stickly protein called fibrin, The secrete a stickly protein called fibrin, which helps to clot blood at the site of a which helps to clot blood at the site of a break.break.

This clot solifies in air and becomes a This clot solifies in air and becomes a scab.scab.

The Blood VesselsThe Blood Vessels

There are 3 major types of blood There are 3 major types of blood vessels, and 2 intermediate types.vessels, and 2 intermediate types.

The major types are The major types are ArteriesArteries VeinsVeins CapillariesCapillaries

Blood Vessels (cont.)Blood Vessels (cont.)

The two The two intermediate types intermediate types are calledare called Arterioles: Vessels Arterioles: Vessels

that link arteries to that link arteries to capillaries..capillaries..

Venuoles: Vessels Venuoles: Vessels that link capillaries that link capillaries to veins.to veins.

Blood vesselsBlood vessels Arteries are the blood Arteries are the blood

vessels that carry blood vessels that carry blood away from the heart.away from the heart.

They are the thickest and They are the thickest and most muscular of all blood most muscular of all blood vessels.vessels.

They need to be able to They need to be able to expand with each beat of expand with each beat of the heart.the heart.

The largest blood vessel in The largest blood vessel in the body, the Aorta, is the body, the Aorta, is considered an artery.considered an artery.

Except for the pulmonary Except for the pulmonary artery, all arteries carry artery, all arteries carry oxygen rich blood which oxygen rich blood which has a bright red color.has a bright red color.

Blood vesselsBlood vessels

Veins are the only Veins are the only blood vessels that have blood vessels that have valves in them.valves in them.

The valves are there to The valves are there to stop the back flow of stop the back flow of blood in your blood blood in your blood vessels.vessels.

Veins carry blood back Veins carry blood back to the heart.to the heart.

Except for the Except for the pulmonary veins, all pulmonary veins, all veins carry oxygen veins carry oxygen poor blood that is a poor blood that is a dark red color.dark red color.

Blood vesselsBlood vessels

The capillaries are the smallest and The capillaries are the smallest and most abudant of blood vessels in your most abudant of blood vessels in your body.body.

It is through the very thin walls of the It is through the very thin walls of the capillaries that all diffusion and osmosis capillaries that all diffusion and osmosis occurs.occurs.

Capillaries pick up nutrients through the Capillaries pick up nutrients through the capillaries surround the S.I., and oxygen capillaries surround the S.I., and oxygen through the alveoli in the lungs.through the alveoli in the lungs.

Arterioles and VenuolesArterioles and Venuoles

These vessels are simply smaller These vessels are simply smaller versions of arteries and veins.versions of arteries and veins.

Their job is the connect larger Their job is the connect larger arteries and veins to the capillaries.arteries and veins to the capillaries.

Arterioles have the same Arterioles have the same characteristics as arteries and characteristics as arteries and venuoles have the same venuoles have the same characteristics of veins.characteristics of veins.

The heartThe heart

The heart is a fist-sized muscular The heart is a fist-sized muscular organ that is found in the center of organ that is found in the center of your thoracic cavity (Chest).your thoracic cavity (Chest).

It is surrounded by a thin protective It is surrounded by a thin protective membrane called the pericardium.membrane called the pericardium.

The heart is protected by the rib The heart is protected by the rib cage.cage.

The heartThe heart

The human heart consists of four The human heart consists of four chambers. In order the blood flows from:chambers. In order the blood flows from: The right atriumThe right atrium The right ventricleThe right ventricle After a round trip to the lungs…After a round trip to the lungs… The left atriumThe left atrium The left ventricleThe left ventricle And then through the Aorta to all the blood And then through the Aorta to all the blood

vessels in the body.vessels in the body.

Superior vena cava

Pulmonary Vein

Circulation.Circulation.

The heart actually consists of two The heart actually consists of two pumps, the right and left ventricles.pumps, the right and left ventricles.

The right ventricle pumps the blood The right ventricle pumps the blood to the lungs and back. This is called to the lungs and back. This is called pulmonary circulation.pulmonary circulation.

The left ventricle pumps the blood to The left ventricle pumps the blood to the entire body and back. This is the entire body and back. This is called systemic circulation.called systemic circulation.

Pulmonary circulationPulmonary circulation

Blood enters the Right Atrium.Blood enters the Right Atrium. It passes through the bicuspid valve into the It passes through the bicuspid valve into the

Right Ventricle.Right Ventricle. The Right ventricle pumps blood into the The Right ventricle pumps blood into the

pulmonary arteries.pulmonary arteries. The pulmonary arteries carry blood to the The pulmonary arteries carry blood to the

lungs.lungs. In the lungs, the blood flows into the In the lungs, the blood flows into the

capillaries surrounding the alveoli. It is here capillaries surrounding the alveoli. It is here the blood picks up O2 and drops off CO2the blood picks up O2 and drops off CO2

Pulmonary circulation cont.Pulmonary circulation cont.

The now oxygenated blood flows The now oxygenated blood flows from the capillaries into veins and from the capillaries into veins and then into the pulmonary veins.then into the pulmonary veins.

The pulmonary veins carry the blood The pulmonary veins carry the blood back into the heart at the left atrium.back into the heart at the left atrium.

This concludes pulmonary This concludes pulmonary circulation, and we begin systemic circulation, and we begin systemic circulation.circulation.

Systemic circulationSystemic circulation

O2 rich blood enters the left atrium.O2 rich blood enters the left atrium. The blood passes through the mitral The blood passes through the mitral

valve and enters the left ventricle.valve and enters the left ventricle. The left ventricle pumps blood into The left ventricle pumps blood into

the aorta.the aorta. The blood flows from the aorta into The blood flows from the aorta into

arteries.arteries. The arteries flow into arterioles.The arteries flow into arterioles.

Systemic circulation cont.Systemic circulation cont.

The blood then flows into the capillaries.The blood then flows into the capillaries. It is here in the capillaries that all It is here in the capillaries that all

diffusion occurs. Nutrients, which were diffusion occurs. Nutrients, which were picked up near the S.I. and O2 from the picked up near the S.I. and O2 from the lungs are delivered to all the cells in the lungs are delivered to all the cells in the body.body.

Wastes and CO2 pass from the cells to Wastes and CO2 pass from the cells to the blood.the blood.

The blood now flows into venuoles.The blood now flows into venuoles.

Systemic circulation cont.Systemic circulation cont.

The blood now enters the veins.The blood now enters the veins. The veins then flow into the vena cava. The veins then flow into the vena cava.

There are two of these.There are two of these. The superior vena cava collects all the The superior vena cava collects all the

blood from the top part of your body, the blood from the top part of your body, the inferior vena cava from the lower part.inferior vena cava from the lower part.

The vena cava delivers the blood to the The vena cava delivers the blood to the right atrium. Systemic circulation is right atrium. Systemic circulation is complete.complete.