The Circulatory SystemJacob Harris, Sam Steakley, Kenneth

Woodworth, Abbey Drummond2nd hour

The Human Circulatory System: What it does

Flow of blood, nutrients, oxygen and other gases, and hormones to and from cells

Fights diseases Maintains a stable environment Also known as the cardiovascular

system Heart, lungs, arteries, veins, coronary

and portal vessels

Artery

Elastic blood vessel that transports blood away from the heart

Two main types: pulmonary and systematic arteries

Veins

Elastic blood vessel that transport blood from various regions of the body to the heart

Pulmonary, systemic, superficial, and deep veins

Size ranges 1 millimeter to 1-1.5 centimeters in diameter

Smallest veins are venules

Capillary

Extremely small blood vessel in the tissues of the body

Transports blood arteries to veins Most abundant in tissues and organs are

metabolically active Red blood cells must travel in single order 5-10 microns in diameter Capillary walls: thin and composed of

endothelium

Platelets

Needed for the formation of a blood clot

Lack a nucleus Life span of 7-12 days Prevents excess loss of blood from a

wound

White Blood Cells

Defend against diseases Larger than red blood cells Squeeze through openings in the walls

of blood vessels May be irregularly shaped and have a

rough surface Several types of white blood cells

Red Bloods Cells

Transport oxygen to cells in all parts of the body

During the formation of a red blood cell, its nucleus and organelles disintegrate

Disk-shaped and concave on both sides

Hemoglobin

Molecule that actually transports oxygen

Iron-containing protein Found in a red blood cell

Plasma

90 percent water Cells receive nourishment from

dissolved substances carried in the plasma

Liquid medium in the bloodstream Carries hormones and brings waste

from the cells to the kidneys or lungs to be removed

Contains variety of proteins

Abnormalities of Platelets

Hemophilia- disorder caused by the absence of one or more of the proteins required for blood clotting People who have hemophilia excessively bleed when injured and could bleed to death

The Heart

Heart - A hollow, cone-shaped muscle located between the lungs and behind the sternum (breastbone).

The heart has three layers. How does blood flow through the

heart? The right and left sides of the heart

work together.

Right Side of The Heart:

Blood enters the heart through two large veins.

As the atrium contracts, blood flows from your right atrium into your right ventricle.

When the ventricle is full, the tricuspid valve shuts.

As the ventricle contracts, blood leaves the heart through the pulmonic valve.

Left Side of The Heart:

The pulmonary vein empties oxygen-rich blood from the lungs.

As the atrium contracts, blood flows from your left atrium into your left ventricle.

As the ventricle contracts, blood leaves the heart.

What is Glucagon?

Glucagon (glū′kă-gon) - Glucagon is a naturally occurring hormone that is produced in the pancreas.

The main function of glucagon is to react to a situation where there is a low level of blood sugar present.

Hormones & Homeostasis

Hormones located in plasma (part of the fluids transported to and from the heart)

Hormones help maintain homeostasis As hormones travel through the

bloodstream regulate how the blood flows

Disorder of the System

The circulatory system is not always perfect.

Examples; Coronary artery disease, hypertension, & rheumatic heart disease.

Hypertension – Technical term for high blood pressure. Blood pressure can be 120 over 80; (TOO HIGH!)

Arteries can burst.