Circulation

Unit 11 – Body Systems

Circulation Blood travels to

every cell in the body – Delivers O2,

nutrients, energy– Removes wastes

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Capillaries of head

and arms

Pulmonary arteryAorta

Superior vena cava

Inferior vena cava

Pulmonary veinCapillaries

of right lung

Capillaries of left lung

Capillaries of lower body

Circulation in Humans

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Capillaries of head

and arms

Pulmonary arteryAorta

Superior vena cava

Inferior vena cava

Pulmonary veinCapillaries

of right lung

Capillaries of left lung

Capillaries of lower body

4 chambered heart Double –loop Pulmonary

Circulation: blood is pumped from the right side of the heart to the lungs

Systemic Circulation: blood is pumped to the body

Human Heart Hollow muscular organ Surrounded by a protective sac called

pericardium Myocardium - muscle in the heart

walls A septum divides the heart in half Each side has 2 chambers

– Atrium (upper) receives blood– Ventricles (lower) pump blood OUT of the heart

Valves keep blood flowing in the right direction

Human Heart

Mitral (Bicuspid) Valve• Prevents backflow from the left ventricle into the atrium

Septum

Right Ventricle

Tricuspid Valve• Prevents backflow between the right atrium and ventricle

Right Atrium

Pulmonary Artery• Carries deoxygenated blood from heart to the lungs

Pulmonary Valve• Prevents backflow between the right ventricle and pulmonary artery

Pulmonary Veins• Carries oxygenated blood from lungs BACK to the heart

Aortic Valve• Prevents backflow into the left ventricle from the aorta

Left Atrium

Left Ventricle

Superior Vena Cava• Large vein which brings O2 poor blood from upper body to the right atrium

Inferior Vena Cava• Large vein which brings O2 poor blood from upper body to the right atrium

Aorta• Brings oxygenated blood from the heart to the rest of the body

Blood Vessels

Blood Vessels -Veins Veins have valves Return blood to the heart

Blood Vessels - Arteries Carry blood Away from the heart Blood is under the highest

pressure in the arteries– Thick muscular walls– Elastic

Artery disease may lead to heart attack or stroke

Blood Vessels - Capillaries Smallest vessels, only one cell thick Diffusion occurs between capillaries and

all cells Gas exchange

What is Blood Pressure?

Pressure exerted by blood against artery walls

Systolic – force when ventricles contract

Diastolic – force felt when ventricles relax

Normal 120/80

What is Heartbeat?

Controlled by the SA Node or “Pacemaker”

How is Heartbeat Measured?

Lymphatic System

Collects fluid that leaks from the blood, and returns it to the circulatory system

Lymph flows through vessels Lymph nodes trap bacteria

Lymphatic System

Two Organs– Spleen removes

old RBCs – Thymus - site

where T-cells mature

Superior vena

cava

Lymph nodes

Thymus

HeartThoracic duct

Spleen

Lymph vessels

Components of Blood

55% Plasma 45% cellular

components– Red Blood Cells

(RBC)– White Blood Cells

(WBC)– Platelets

Components of Blood What does each component look like?

What is the structure? What is the function of each

component? (plasma, RBC, WBC, platelets)

How does structure determine function? Which cells are the most numerous? What is the scientific name for each cell

type?

Components of Blood Red Blood Cells (Erythrocytes)

– Iron containing hemoglobin binds O2

– Disc shape increases surface area– Most numerous cell type

White Blood Cells (Leukocytes)– Fight infection– Largest blood cell, least numerous

Platelets (Thrombocytes)– Release chemicals to clot blood– Small cellular fragments

Blood Cells

Red Blood Cells White Blood Cells Platelets

Blood Types

Incompatible blood types will result in agglutination (clumping)

Blood Types

A, B, AB, and O

OAnti-A &Anti-B

NoneO

ABA, B, AB and O

NoneABAB

B and AB

O and BAnti-ABB

A and AB

O and AAnti-BAA

Can Donate To…

Can Receive Blood From…

Antibodies in Plasma

Antigens on RBC’s

Blood Type