The Circulatory Systemalso known as The Cardiovascular System

Functions of the Circulatory System

• Delivers substances to cells• Removes waste from cells• Transports hormones• Helps fight disease• Regulates body temperature

Parts of the Circulatory System

• Blood• Heart• Blood Vessels

Position of the Heart

External Anatomy of the Heart

Internal Anatomy of the Heart

The Heart

• Muscular organ about the size of your fist• Pumps oxygen-poor blood to the lungs and

oxygen-rich blood to cells in the body• 4 Chambers: 2 Ventricles and 2 Atria• Valves are flaplike structures that open and

close to allow or disallow the flow of blood, keeping it flowing in one direction

Heart Facts

• Heart beats 100,000 times a day– 35 Million times per year– 2.5 Billion times in a lifetime

• One blood cell cycles through the heart 3 times per day!

Three Types of Blood Vessels

• Blood vessels transport blood through the body– Arteries– Veins– Capillaries

Arteries

• Carry blood that is high in oxygen (except for the Pulmonary arteries)

• Carry blood that is low in waste products (except for the pulmonary arteries)

• Carry blood away from the heart

• Contain smooth muscle• Most are found deeper in

the body

Aorta

Coronary Artery

Veins

• Low in oxygen ( except for the pulmonary veins)

• High in waste products such as CO2 ( except for the pulmonary veins)

• Carries blood back to the heart

• Made of smooth muscle• Thinner than arteries• Many are found closer to

the surface

Veins Contain Valves

• Blood flow must “defy gravity” to travel back to the heart

• Valves prevent the blood from moving backwards

Veins

• Veins are located near skeletal muscles

• As skeletal muscles contract they help push the blood toward the heart

Capillaries

• Smallest vessels – only one cell thick!

• Include both vein and artery capillaries

• The only vessel that lets blood in or out

• Capillaries are very close to individual body cells (no more than 3 or 4 cells away)

Blood Flow Through the Body

Right Atrium• Oxygen poor blood comes

FROM the body and dumps into the Right Atrium

Blood Flow Through the Body

Right Ventricle• Oxygen poor blood leaves

the right atrium and is pumped into the RIGHT VENTRICLE

Right Ventricle to the Lungs!

In the Lungs the RBC’s get Oxygen

Lungs to Left Atrium

• After the RBC’s pick up oxygen from the lungs they go back to the heart

• The oxygen rich blood flows to the Left Atrium

• It stays in the left atrium until the heart contracts and squeezes it into the ...

Left Ventricle!

• The Left ventricle receives Oxygen rich blood from the Left Atrium.

• Then the Left Atrium contracts and squeezes the oxygen rich blood out to the body

Blood Vessels Connect to Body Cells

Structures & Functions of Blood

• Analytical– Write a detailed response to answer the question: How do the

structures of the blood enable them to perform their functions?• Creative

– Create a model of blood flowing inside of a blood vessel depicting the various blood cells and their shapes/colors; label each blood cells and write a caption that describes its appearance and job

• Practical– Research two different diseases of the blood, describe effects

on parts of the blood, effects on the body, and possible treatments• Leukemia, Hemophilia, Anemia or Sickle Cell Anemia