Par Heart and Lungs

How does exercise effect the cardiorespiratory

system?

• cardiac output

• capillary supply

• blood volume

• ventilation

Cardiovascular anatomy…

heart, peripheral circulatory system, RBCs

What does the cardiovascular system do

• supplies muscles and organs with O2

• removes metabolic by-products from tissues

• critical for performance

Heart muscle layers…

endocardium, myocardium, epicardium, pericardium

Endocardium

innermost, lines heart cahmbers, allows smooth blood flow

Myocardium

middle, think and muscular, pumps blood

Epicardium

outer, thin, protective

Pericardium

protective outer sac, loosly surrounds heart

Right ventricle has…

deoxygenated blood, and sends it to the lungs via the pulmonary artery

Left ventricle has…

Oxygenated blood, send it to the body via the aorta

right atrium has…

• Deoxygenated blood from body

• Via superior/inferior

vena cava

left atrium has…

• Oxygenated blood from lungs

• Via pulmonary vein

Semiulnar valves…

Open when ventricles contract to direct blood flow into arteries

Pulmonary valve

R vent> Pulmonary artery

Aortic valve

L vent> aorta

Blood Pathway

1. Blood into R atrium via sup/inf vena cava (Deox)

2. Blood flows to right ventricle via tricuspid valve (Doex)

3. R vent pumps blood to lungs through pulmonary valve via pulmonary artery (Deox)

4. Blood into L atrium from lungs via pumonary vein (OX)

5. L atrium pumps blood to L vent via bicuspid valve (OX)

6. L vent pumps blood to the body through aortic valve, via aorta

What is the sinus node?

• Bundle of nerve fibers that control heart rate

• inside right atrium wall

• Generate a nerve impulse (action potential)

• Causes muscle walls to contract

Systolic BP

• During ventricular contraction (systole)

• How hard heart works

• Strain against arterial walls during contraction

Top number

Diastolic BP

• During heart relaxation (diastole)

• Indicates peripheral BP (outside the heart)

• Ease with which blood flows from arterioles to

capillaries

hypertension is…

high blood pressure

What is cardiac output?

• Amount of blood pumped by heart into aorta each minute

• Quantity of blood that flows into peripheral circulation

Stroke vol * Heart Rate = Cardiac output

What is stroke volume?

• Amount of blood (ml) pumped out of left ventricle per heartbeat

• Resting: 70 ml

What is heart rate?

• Rhythmical contraction of the heart walls (beats per minute, bpm)

• Resting: 40-70 bpm

What is intensity of work?

• Estimated by measuring heart rate via carotid or radial pulse

Peripheral circulatory system consists of…

• Consists of blood vessels made up of layers of tissue

• Smooth muscle cell layer allow vessels to contact

• This regulates blood flow throughout the body

Arteries carry blood____ from the heart

away

Arterioles are…

Small vessels that branch from arteries

Capillaries are…

• Tiny vessels that branch from arterioles

• Composed only of endothelial cells

• O2, nutrient, by-products exchange

Veins carry blood____the heart

towards

Venules are…

Small vessels that branch from veins

valves do….

• Open with blood flowing towards heart

• Close with blood flowing away from heart

prevent backflow

Plasma is…

transport fluid

Platelets are..

the clot forming component

white blood cells are…

infection fighting cells

RBC make up ___% of blood volume

45%= hematocrit

RBCs carry O2 from ____>____

lungs to body tissues

RBCs carry CO2 from ____>____

body tissues to lungs

Transport of CO2

Tissues>blood>lungs>air

Transport of CO2 helps regulate

• Ionic equilibrium (chloride shift)

• Ph balance (bicarbonate)

O2 uptake is…

VO2, Amount of O2 consumed due to aerobic

metabolism, measured as O2 volume consumed in one minute

Calculation of VO2 max

= cardiac output (central component, amnt of O2 delivered by cardio system) * a-v O2 difference (peripheral component, amnt of O2 extracted by skeletal msc)

2 factors affecting O2 delivery

1. cardiac output

2. hematocrit

What is cardiac output?

• Amount of blood pumped by the heart

• Determines O2 volume delivered to tissues

what is hematocrit?

• Concentration of red blood cells

• Determines amount of O2 per a volume of blood