The Human Circulatory

System

SBI 3U

• E2.2 perform a laboratory or computer-

simulated dissection of a representative

animal, or use a mounted anatomical model, to

analyse the relationships between the

respiratory, circulatory, and digestive

systems [PR, AI]

• E2.3 use medical equipment (e.g., a

stethoscope, a sphygmomanometer) to

monitor the functional responses of the

respiratory and circulatory systems to

external stimuli (e.g.,measure the change in

breathing rate and heart rate after exercise)

[PR, AI]

• E3.3 explain the anatomy of the circulatory

system e.g., blood components, blood

vessels, the heart) and its function in

transporting substances that are vital to

health

• E3.4 describe some disorders related to the

respiratory, digestive, and circulatory

systems (e.g., asthma, emphysema,ulcers,

colitis, cardiac arrest, arteriosclerosis)

For Consideration

• Functions

• Circuits

• Components

Heart, Blood, Veins and Arteries, Capillaries

• Cardiac Cycle

• Heart Beats

• Blood Pressure

Human Circulatory System

Closed System

• blood never leaves the

network of blood

vessels

• O2, CO2, and

nutrients are diffused

from blood into

tissues

Functions

• Transport of oxygen and carbon dioxide

• Distribution of nutrients and transport of wastes

• Maintenance of body temperature

• Circulation of hormones

• Protection against blood loss from injury

The Human Heart

The Human Heart

• Has 4 chambers where blood fills

• Top chambers are called atria

• Bottom chambers are called ventricles

• Atria and ventricles are separated from each other via a

septum (thick muscular wall)

• Valves in the heart prevent blood from flowing the wrong

way

• Pumps blood through the body via a network of veins and

arteries

3 Main Circuits

• Pulmonary Circulation

• Coronary Circulation

• Systemic Circulation

Coronary Circulation

• Oxygen rich blood is pumped within the heart muscle

Pulmonary Circulation

• Oxygen poor blood is pumped into the lungs

• Oxygen rich blood is carried back to the heart

Systemic Circulation

• Oxygen rich blood is carried to body tissues

• Oxygen poor blood is carried back to the heart

Pulmonary and Systemic

Systems

Pulmonary and Systemic

Systems

Blood Flow Activity

Blood

• Made up of 4 Components

1. Plasma

2. White Blood Cells

3. Platelets

4. Red Blood Cells

Red Blood Cells

• Deliver oxygen to the body tissues received from lungs and remove

carbon dioxide from the bodies tissues

• Red only because they contain a protein chemical called hemoglobin

which is bright red in color

• Hemoglobin contains the element Iron, making it an excellent vehicle

for transporting oxygen and carbon dioxide

• The average life cycle of a red blood cell is 120 days

White Blood Cells

• Also called Leukocytes

• Protect the body from disease

• Will produce antibodies in the body to fight off germs and

infection

Platelets

• Platelets are irregularly-shaped, colorless bodies that are

present in blood. Their sticky surface lets them, along

with other substances, form clots to stop bleeding.

• The mineral calcium, vitamin K, and a protein called

fibrinogen help the platelets form a clot.

Plasma

• Liquid component of blood which is 90% water

• contains blood proteins, glucose, vitamins, minerals, dis-

solved gases, and waste products of cell metabolism.

• Proteins help maintain body homeostasis

Capillaries

• one epithelial cell thick

• exchange of oxygen and carbon dioxide takes place

through the thin capillary wall.

• red blood cells inside the capillary release their oxygen

which passes through the wall and into the surrounding

tissue.

• tissue releases its waste products, like carbon dioxide,

which passes through the wall and into the red blood

cells.

Capillary Exchange

Cardiac Cycle

Heart Beat

• is controlled by a nerve impulse called the Sino atrial node (SA node).

• The SA node is also referred to as the natural pace maker.

• . The “lub” sound is produced when the tricuspid and mitral valves open and close.

• The “dub” sound occurs when the pulmonary and aortic valve open and close.

Heart Beat

• http://chs.sd57.bc.ca/~jbleecker/science/bi12ppt/Bio12_2/

C13_Circulatory%20System_Newer/cardiac.swf

Heart Rate

• An electrocardiogram (ECG) is a test that measures the electrical activity of the heart.

• A normal resting heart rate is 70 beats per minute with a consistent and even rhythm

• As you know, your heart rate can fluctuate throughout the day.

• Factors affecting HR can include exercise, sleeping, emotions, drugs and.

Blood Pressure

• A sphygmomanometer is used to measure blood

pressure. The normal average blood pressure reading is

120/80. The systolic pressure is always recorded first.

High Blood Pressure

High blood pressure is dangerous because:

• pressure the blood places on the vessels may cause them to burst

• narrowing of the artery.

• build up of plaque on the arterial walls.

• High blood pressure can generally be reduced by making lifestyle changes such as exercise and healthy diet

Measuring BP

Other Things to Consider

Circulatory Conditions

• Angina

• Atherosclerosis

• Arrythmias

Lymphatic System

Resources

• www.innerbody.com

• www.youtube.com

• Nelson Biology 11 Text