Part 1

Anatomy of Blood and the Heart

Chapter 9: The Circulatory System

What’s in your blood?Functions of Blood CellsAnatomy of the Heart

Learning Objectives

The heart pumps blood throughout your body

Blood picks up and drops off different substances to ensure that cells have oxygen and carbon dioxide as well as other waste products are properly disposed of

Purpose of the Circulatory System

Considered a connective tissue

When your blood is centrifuged (spun really fast) it separates materials by density

Your blood consists of a liquid component called plasma

You blood also consists of 3 formed componentsRed Blood CellsWhite Blood CellsPlatelets

Your Blood

92% is water8% is made of plasma

proteins, salt, nutrients, urea, hormones and vitamins

3 Types of Plasma ProteinsAlbumin – maintains

proper osmotic pressure

Fibrinogen – helps with clotting

Immunoglobulin – AKA antibodies

Plasma

AKA ErythrocytesRBCs contain a

protein called hemoglobin which carries oxygen

Oxyhemoglobin is bright red (makes your arteries look red)

Deoxyhemoglobin is purplish-blue (makes your veins look blue

Live for about 4 months

Red Blood Cells

AKA leukocytesNot as many WBCs as

RBCsFight off invading

microbes, bacteria, viruses

Two main types of WBCsGranular LeukocytesAgranular

Leukocytes

White Blood Cells

White Blood Cell FunctionsType of White Blood Cell Specific Functions

Granular Leukocytes

Eosinophils Numbers increase during allergic reactions and parasitic infections

Neutrophils First to respond to infections - phagocytize

Basophils Seep out of vessels at site of injury and release histamine to dilate vessels

Agranular Leukocytes - Lymphocytes

B lymphocytes Form antibodies to fight infection

T lymphocytes Destroy cells that contain foreign material

Monocytes Mature into macrophages, engulf disease-causing microbes, stimulate other WBCs into action

White Blood Cells

AKA thrombocyteTiny fragments of cellsLarge cells in the bone

marrow called megakaryocytes break into fragments which are platelets

Help the clotting process by plugging up the injured blood vessels

Platelets

Main organ of the circulatory system

The heart is the driving force behind the movement of the blood

The pressure is generates by the pumping action, forces the blood through the vessels

The heart lies between the lungs and behind and slightly to the left of the sternum

The Heart

Pericardium/Pericardial Tissue: thick layer of muscle tissue and a protective membrane that folds into two layers surrounding the heart

Endothelial Tissue: endothelial tissue that lines the inside of the heart and is continuous with all your blood vessels

Layers of the Heart

Pericardial Cavity: Coronary vessels – blood vessels that supply the tissues of the heart with nutrients and oxygen

Myocardium: muscular layer of the heart

Layers of the Heart

Epicardium: inner layer of the pericardium, covers the myocardium and secretes perocardial fluid to help lubricate so tissues don’t rub together during contraction

Parietal Pericardium: outermost layer of the heart, thin, white, fibrous connective tissue that joins the major blood vessels

Layers of the Heart

Right AtriumLeft AtriumRight VentricleLeft VentricleInteratrial

Septum – wall dividing the two atria

Interventricular Septum – wall dividing the two ventricles

4 Chambers of the Heart

The heart contains several valves

Valves keep blood flowing in the right direction on the pathway and allows the right amount of blood into each chamber

The names of the valves can tell you their location or certain characteristics

Semilunar Valves - half moons

Atrioventricular Valves (AV) – between the atria and ventriclesBicuspid Valve – 2 flapsTricuspid Valve – 3 flaps

Heart Valves

What are the 3 formed components of blood?List some of the types of white blood cellsWhat is the name of the thin fibrous tissue

that covers the heart?What are the four chambers of the heart?Under what conditions does blood look

purplish blue?What types of substances are carried in

plasma?What is the purpose of the circulatory system?

Review Questions