Circulatory System

BellList the functions of the circulatory and respiratory systems.

Learning Target

I can identify the components of the circulatory system.

The circulatory system is composted of blood, blood vessels, lymphatic system, and the heart.

Together they serve as a transportation system, where materials are transported to and from the cells.

Blood

The fluid circulated through the circulatory system by the heart.

8 percent of the total weight of an animal is blood.

The blood is closed of plasma, blood cells, and palates.

Plasma

The fluid component of blood that accounts for 50-60 percent of the bloods volume.

Plasma is approximately 90 water.The remaining 10 percent consist

of small amounts of digested food nutrients, hormones, gases, and waste products.

Blood Cells

Blood cells are neither red or white.

Red Blood Cells

Red blood cells or erythrocytes, are formed in the red bone marrow.

These cells contain hemoglobin, an iron containing protein.

Hemoglobin

Hemoglobin aids in the transport of oxygen and carbon dioxide and is responsible for giving blood its red color.

White blood cells

White blood cells, or leucocytes, are fewer in number than the red blood cells but are larger in size.

Difference in white & red blood cells

WHITE BLOOD CELLS

Have nucleus Motile Not confined to the

blood Will move to areas

of inflammation to engulf and destroy invading organisms

YouTube - White Blood Cell Chases Bacteria

RED BLOOD CELLS

No nucleus Not motile Confined to the blood

Platelets

Platelets are small and easily damaged blood cells that occur in large numbers in the blood.

They attach themselves to injuries in blood vessels of damaged tissue and will release enzyme.

Fibrinogen

The enzyme leads to the formation of fibrinogen.

Fibrinogen is the vital component in the clotting of blood

Blood vessels are divided into two circulatory subsystems

SYSTEMIC SYSTEM

Transports blood to all body tissues except the lungs

PULMONARY SYSTEM

Transports blood to the lungs and back to the heart.

YouTube - Systemic and Pulmonary Circulation

There are three types of blood vessels

ArteriesCapillariesVeins

Arteries

Blood vessels that carry blood away from the heart.

Arteries carry oxygenated blood to body tissues, except the pulmonary artery.

Arteries divide into smaller branches called arterioles.

Arterioles carry blood to capillaries

Capillaries

Tiny blood vessels that connect arteries with the veins.

Nutrients and oxygen diffuse through the capillary walls into body tissues.

Carbon dioxide and other waste products pass through the capillary walls and are carried away from body tissue.

Veins

Blood vessels that carry blood toward the heart.

Blood flow in veins is only permitted to flow towards the heart; this is controlled by valves that open at regular intervals.

Lymphatic System

Consist of the lymph vessels, lymph nodes, and lymph fluid, returns excess lymph to the circulatory system.

Lymph filters through the capillary walls into the spaces between the cells to take nutrients and hormones to cells to carry waste products back to the circulatory system.

Lymph nodes filter out infectious organisms such as bacteria and viruses.

Swollen lymph nodes are often a sign of disease.

Heart

The heart is the major organ of the circulatory system.

The heart consist of three layers, the myocardium, endocardium, and the epicedium.

YouTube - Heart4