1. Cardiovascular System

2. Circulatory System
The circulatory system includes the heart and all the blood vessels that circulate throughout the body.

3. Circulation is divided into two circuits:
The pulmonary circuit carries blood between the lungs and the heart.
The systemic circuit carries blood between the heart and the rest of the body.

4. Arteries carry blood away from the heart.
Smaller lumen, thicker wall with more smooth muscle.
Veins carry blood towards the heart.
Larger lumen, thinner wall.

5. Veins have built-in valves to prevent blood from flowing back down, since they usually flow against gravity.
Skeletal muscle will also “milk” or squeeze the veins to help the blood move up.

6. Capillaries are the smallest blood vessels, many only allow erythrocytes through single-file.
Found anywhere oxygen and carbon dioxide are exchanged.

7. The heart provides the force that propels blood through the body.
The heart is a double-pump. Each side beats separately:
The right side (pulmonary) pumps blood to the lungs.
The left side (systemic) pumps blood to the rest of the body.

8. Right Atrium
Left Atrium
Right Ventricle
Left Ventricle
Superior Vena Cava
Inferior Vena Cava
Aorta
Pulmonary Trunk
L. Pulmonary Artery
R. Pulmonary Artery
R. Pulmonary Veins
L. Pulmonary Veins
Coronary Artery

9. Aorta
Right Pulmonary Artery
Left Pulmonary Artery
Superior Vena Cava
Left Pulmonary Veins
R. Pulmonary Veins
Left Atrium
Coronary Sinus
Pulmonary Semilunar Valve
Aortic Semilunar Valve
Right Atrium
Bicuspid Valve
Tricuspid Valve
Left Ventricle
Right Ventricle
Inferior Vena Cava

10. The heart has four valves that allow blood to move forward while preventing backflow.

11. The Pacemaker
Cardiac muscle cells are able to contract in a regular pattern without any input from the brain.
The sinoatrial node, also known as the pacemaker, creates an electrical impulse that spreads through the rest of the heart.

12. The impulse from the SA node stimulates the left and right atria to contract first.
The atrioventricular node then receives the signal and passes it through the ventricles.
The heart will naturally contract at a rate of beats per minute.

13. Electrocardigrams
Electrocardiograms, or ECGs, measure the electrical impulses coming from the heart, creating a graph of the output.

14. Reading an ECG
Each change on the ECG is given a letter label and corresponds to a specific change in the heart.
P wave: Atria contract.
QRS wave: Ventricles contract.
T wave: Ventricles relax and reset.

15. An arrhythmia is any irregular heartbeat pattern that does not follow the normal P-QRS-T pattern.
Atrial fibrillation is a rapid and irregular heartbeat.
Bradycardia is a heart rate that is too slow (below 60 beats/min at rest)
Tachycardia is a heart rate that is too fast (above 100 beats/min at rest)

16. Blood Pressure
Blood pressure is the force that blood exerts on the blood vessels.
Systolic pressure is measured when the ventricles contract and push blood through the arteries.
Diastolic pressure is when the ventricles relax and begin refilling.
The normal blood pressure range is /

17. If a blockage occurs in a coronary artery, this causes a heart attack.
Atherosclerosis a buildup of lipids, calcium, or cell debris that gradually restricts bloodflow.
If a blockage occurs in a coronary artery, this causes a heart attack.
The portion of the heart supplied by its blood will die.

18. Bypass
A bypass involves transplanting a vein from another part of the body (usually the leg) onto the heart.
Blood is re-routed around the blockage.

19. Angioplasty
A narrow balloon is inserted into the blocked vessel. It is then inflated, expanding the vessel.

20. If the vessel does not stay expanded on its own, a mesh-like stent can be inserted to hold it open.

22. Fetal Circulation
In an adult, blood flows from the right atrium to the right ventricle, then out to the lungs.
In a fetus, the lungs are nonfunctional and can be bypassed.
The foramen ovale is an opening that allows blood to move directly from the right to left atrium.

23. Fetal Circulation
The fetus receives all of its oxygen and nutrients from the mother through the umbilical vein.

24. Fetal Circulation
Carbon dioxide and other wastes produced by the fetus are returned to the mother through the umbilical artery.

25. Fetal Circulation
Fetal blood has a much greater (+50%) concentration of hemoglobin with a higher affinity for oxygen than maternal blood.
After birth, more blood flows into the pulmonary arteries and veins, increasing pressure in the left atrium.
This forces the foramen ovale to permanently close.

26. Systemic Circulation
Each time an artery or vein forms smaller branches, it is given a new name.

27. External Carotid
Internal Carotid
Common Carotid
Subclavian Artery
Brachiocephalic Artery
Renal Artery
Abdominal Aorta
Common Iliac
Internal Iliac
External Iliac Artery
Femoral Artery

28. Internal Jugular
External Jugular
Brachiocephalic Vein
Subclavian Vein
Superior Vena Cava
Hepatic Vein
Inferior Vena Cava
Renal Vein
Common Iliac Vein
Internal Iliac Vein
Femoral Vein

29. Circulatory Pathway in the Human Body
Section 1 The Circulatory System
Chapter 46
Circulatory Pathway in the Human Body

30. Chapter 46 Lymphatic System
Section 1 The Circulatory System
Chapter 46
Lymphatic System
The circulatory system also includes the lymphatic system.
The lymphatic system returns fluids that have collected in the tissues to the bloodstream.
Excess fluid in the tissues, called lymph, moves into the tiny vessels of the lymphatic system by diffusion.

31. Lymphatic System, continued
Section 1 The Circulatory System
Chapter 46
Lymphatic System, continued
Lymph vessels are similar to blood vessels but are also different in many ways.
Lymph is filtered through small organs known as lymph nodes to trap tissue debris and other foreign particles.
Lymph nodes also store lymphocytes, white blood cells that are specialized to fight disease.

32. Section 1 The Circulatory System
Chapter 46
Lymphatic System