Chapter 5. Cardiovascular System: Heart and Blood Vessels

The cardiovascular system enables body systems and cells to exchange materials withthe external and internal environments. [Figure 5.1]

External exchange –

Internal exchange –

Structural Components of the Circulatory System: Heart.Blood vessels.

Arteries –

Veins –

Capillaries –

A capillary bed. [Figure 5.2]

Blood. Blood is a liquid tissue. Why is it classified as a type of connective tissue?

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The lymphatic system.Function of the lymphatic system –

[Figure 7.6 with modifications]

The Heart – A double pump.External view. [Figure 5.3]

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Adapted from Campbell, N. & J. Reese. Biology, 7 ed. 2005. Pearsonth

Education, Inc.

The path of blood into and through the heart:The colors below indicate oxygen poor (blue) and oxygen rich (red) blood.

Superior vena cava and inferior vena cava (blood from the upper and lower body)�

Right atrium�

(Right atrioventricular valve)�

Right ventricle�

(Pulmonary semilunar valve)�

Pulmonary trunk (artery tolungs)

�Pulmonary veins (veins fromlungs)

�Left atrium

�(Left atrioventricular valve)

�Left Ventricle

�(Aortic semilunar valve)

�Aorta (artery to upper andlower body)

Terms to note: Cardiac refers to the heart.Pulmonary refers to the lungs.

The beating of the heart – The cardiac cycle.Systole – Diastole –

Stages of the cardiac cycle. [Figure 5.5]Heart sounds –

What causes the heart sounds?

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Adapted from Campbell, N. & J. Reese. Biology, 7 ed.th

2005. Pearson Education, Inc.

Adapted from Hole, J.W. Human Anatomy and Physiology, 6 ed. 1993. Wm. C.th

Brown, Inc.

Heart Beat:The heart has an inherent rhythm. ???

Controlled by centers in brain.The Pacemaker –

Adrenal hormones epinephrine andnorepinephrine stimulate heart.

Electrical activity of the heart and the electrocardiogram (ECG):

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Blood Pressure:Systolic pressure –

Diastolic pressure –

Blood Vessels: [Figure 5.2]Veins –

Arteries –

Capillaries –

Adapted from Hole, J.W. Human Anatomy and Physiology, 6 ed. 1993. Wm. C. Brown, Inc. th

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Veins have little blood pressure.

What causes varicose veins?

Two cardiovascular pathways.[Figure 5.10] < Pulmonary circuit. < Systemic circuit.

Portal systems.What is a portal system?

The hepatic portal system.[Term: Hepatic refers to the liver]

Locate the hepatic portal system on thedrawing to the right.

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Tissue fluids and the lymphatic system. [Figure 5.12]

Fluid exchange at the capillary level.

Excess fluids collect in lymphatic vessels. [Figure 5.13]

Cardiovascular Disorders:Atherosclerosis: The development of plaquewithin arteries. [Figure 5.14]

Plaque –

(Arteriosclerosis: A hardening of the arteriesdue to an accumulation of plaque on theirinner lining.)

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Bypasses and stents.[Figure 5.15 modified]

Myocardial infarction –

Coronary thrombosis –

Thrombus –

Embolus –

Heart transplants –

Artificial hearts [Figure 5.16] –

Genetically modified pigs?

More terms associated with cardiovascular disorders: 1. Tachycardia –

2. Bardycardia –

3. Fibrillation –

4. Aneurysm –

5. Stroke –

6. Low blood pressure. Is it a problem?

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