Circulatory SystemMain Functions:

1. Transports nutrients, hormones, & gases

2. Get rid of wastes

3. Helps maintain a constant body temperature

Two Systems make up the Circulatory System:

1. Cardiovascular system: the blood, heart, & blood vessels.

2. Lymphatic system: the lymph, lymph nodes, & lymph vessels.

Cardiovascular System

Function: the heart pumps oxygen rich blood throughout the body and returns oxygen poor blood to the lungs.

Lymphatic System

Function: returns fluids (lymph) that have collected in the tissues to the bloodstream.

Lymph nodes (mini filters) store lymphocytes.

Circulation Pattern & Heart Structures

-Flow

-Valves

Heartbeat ControlSinoatrial Node (SA Node) located in the right atrium.

“pacemaker”

Atrioventricular Node (AV Node) located in the upper septum.

Blood Pressure:-systolic pressure- when the ventricles contract-diastolic pressure- when the ventricles are relaxed

Pulse: Pressure waves in arteries from contraction of the left ventricle

Hypertension- high blood pressure!

Blood Vessels

AortaArteriesArterioles

Capillaries -Microscopic blood vessels.

-Walls are one celled thick

-Blood cells move through in single file line.

-Capillary walls enable nutrients and gases to diffuse easily between blood cells and surrounding tissue cells.

VeinsVena CavaVeinsVenules

-Veins unlike arteries have valves.

Patterns of CirculationPulmonary CirculationSystemic CirculationCoronary Circulation Hepatic Portal Circulation Renal Circulation

Flow of Blood

Blood (Ch. 46.2)

Plasma- liquid part of the blood, mostly water. Carries nourishment for the cells.

Red Blood Cells (erthrocytes)- transport oxygen. Formed in the red marrow of cells.

-Hemoglobin- transport oxygen and carbon dioxide.

-no nuclei-life span of 120-130 days

White Blood Cells (leukocytes)- help defend the body against disease.

-formed in the red marrow, lymph nodes, and spleen.-larger than RBC’s-can live many years

Platelets- help form blood clots.

-Fibrin (protein) is produced that forms a sticky web, forming a clot.

Blood Types- A, B, O, AB– Antigens- protein or carbohydrate that signals the body

that something foreign has entered it.– Rh factor- antigen present on the surface of RBC’s.

Majority of humans are Rh +.

Structure of a Heartbeat