1. Cardiovascular System
Chapter 12

2. The big idea Why is the cardiovascular system important?
The cardiovascular system pumps blood which carries oxygen and removes CO2 from the tissues of the body.

3. Parts of the System
Heart
Blood Vessels
Blood

4. Anatomy of the Heart Located in the Thoracic Cavity
The heart is a muscle (cardiac muscle)
Main Function: Pump Blood
The Human heart has four chambers
Left Atrium
Right Atrium
Left Ventricle
Right Ventricle

5. Anatomy of the Heart Atria – receiving chambers of the heart
Left receives blood from the lungs
Right receives from the body
Ventricles – sending chambers of the heart
Left sends blood to the body
Right sends blood to the lungs
Interventricular septum separates the two

8. Anatomy of the Heart Operation of Blood Valves
Atrioventricular (AV) valves – between the Atrium and ventricle
Tricuspid valve – right side
Bicuspid valve – left side
always open until the ventricles contract
Contraction pressure forces them to shut

9. Anatomy of the Heart
Semilunar valves – valve leading out of ventricles
Normally closed until ventricle contraction opens it

11. Anatomy of the Heart Major Blood Vessels of the Heart :
Vena Cava – carry deoxygenated blood from body to heart
enters right atrium
Aorta – delivers oxygenated blood from heart to body
exits left ventricle

12. Anatomy of the Heart
Pulmonary Veins – delivers oxygenated blood from lungs to heart
Enters left atrium
Pulmonary Arteries – carries deoxygenated blood from heart to lungs
Exits right ventricle

15. Physiology of the Heart
Heart beats 115,200 times a day
How does the heart contract (pump)?
Bundles of nerve fibers stimulate the muscle to contract
The main bundle is the SA node (this is our natural pacemaker)
Electrocardiogram (ECG) – measure the electrical activity of heart beats
Ineffective valves can cause a heart murmur.

17. Anatomy of the Blood Vessels
Function: transport blood & contents
Types of Blood Vessels:
Arteries – transport blood away from heart
Veins – transport blood to the heart
Capillaries – microscopic vessels where gas exchange occurs

18. Anatomy of the Blood Vessels
Size of vessels (large to small)
Arteries  arterioles  capillaries
Veins  venules  capillaries
Major arteries: Aorta, Pulmonary Artery
Major Vein: Vena Cava, Pulmonary Vein

20. Anatomy of the Blood Vessels

21. Anatomy of the Blood Vessels

22. Physiology of the Blood Vessels
It only takes one minute for a drop of blood to go from the heart to the foot and back to the heart!
Blood moves from areas of high pressure to areas of low pressure
Blood pressure – is the force of blood against a blood vessel wall

23. Physiology of the Blood Vessels
Factors that affect blood pressure: (pg 236)
Amount of blood leaving the heart
Peripheral resistance – friction
Size of vessels
Length of vessels
Obese individuals are prone to high bp
For one extra pound of fat, 200 miles of blood vessels develop

24. Evaluating Circulation
Heart Beat
Stethoscope
Pulse
Pulse points: pg. 238
Blood Pressure
sphygmomanometer

25. Anatomy of the Blood Composed of 2 basic components
Cells (red, white, platelets) = 45%
Plasma (water, amino acids, vitamins, hormones, electrolytes, cellular waste) = 55%

26. Anatomy of the Blood
Erythrocytes (red blood cells) – transport oxygen and carbon dioxide
Hemoglobin – protein that binds with gases
Iron is an important part
Oxyhemoglobin – full of O2 (bright red)
Deoxyhemoglobin – not carrying O2 (dark red)
Shape: concave discs

27. Anatomy of the Blood About 5 million per cubic millimeter
No nucleus…they must be made in the bone marrow
Erythropoetin (EPO) – is a hormone that increases RBC production
Anemia – condition where there are too few blood cells

28. Anatomy of the Blood Blood Facts
Heart Labeling Practice

29. Chapter Review Pg. 252 Study Q’s - # 1, 3, 8, 9, 11
Objective Q’s - # 1-4, 9, 12

30. Sheep Heart Dissection
Part 1 – External anatomy of heart
Part 2 – Internal anatomy of heart