1. The Circulatory System

2. Functions of the Circulatory System
Brings blood containing oxygen and nutrients to cells
Transports CO2 and other wastes away from cells
Fights infection
Regulates body temperature

3. Circulatory System Components
Heart
Blood
Vessels
Arteries
Veins
Capillaries

4. The Heart A muscular pump Moves blood through the body
Has four chambers
Aorta
Left pulmonary artery
Left atrium
Left pulmonary
veins
Left ventricle
Superior vena
cava
Right pulmonary
Right atrium
Right ventricle
Inferior vena cava
Divided into right and left halves
Made up of cardiac muscle cells

5. Structures of the Heart
Chambers
Atria- (2) upper chambers
Thin walled
Receive blood from veins
Send blood to ventricles
Ventricles- (2) lower chambers
Thick walled
Receive blood from atria
Pump blood out through arteries
Septum
Pulmonary valve
Right atrium
Tricuspid valve
Right ventricle
Left atrium
Aortic valve
Mitral valve
Left ventricle
Septum
Wall that divides heart into right and left halves

6. Pathway of Circulation
Oxygen-poor blood draining from the body through veins into the superior and inferior vena cava flows to the right atrium, through the tricuspid valve, and into the right ventricle.
As the right ventricle contracts, oxygen-poor blood passes through the pulmonary valve into the pulmonary arteries and on to the lungs to receive oxygen.

7. Pathway of Circulation
Oxygen-rich blood from the lungs enters the heart through the pulmonary veins, passing into the left atrium.
Then through the mitral valve to the left ventricle. Contraction of the left ventricle forces blood through the aortic valve into the aorta.
Various arteries branch off from the aorta to supply blood to all parts of the body.

8. Pathway of Circulation
Nutrients pass into tissues
Waste products filter back
Blood pumped out of
heart into arteries,
which branch into
smaller and smaller
vessels until blood flows
into capillaries
Blood returns to the
heart through the veins
Heart
Capillary
network
Arteries branch into smaller and smaller vessels (arterioles).
They eventually become capillaries, which supply blood to all body parts.
Capillaries merge and join veins to carry blood back to the heart.

9. Blood Vessels
Form a closed circuit of tubes that carry blood throughout the body
Laid end to end, the blood vessels in an average human body will stretch approximately 62,000 miles……2.5 times around the earth

10. Blood Vessels Arteries Receive blood from ventricles
Take blood away from the heart
Usually carry oxygenated blood
Aorta is the largest artery

11. Blood Vessels Veins Transport blood away from capillaries
Carry blood toward heart
Usually carry de-oxygenated blood
Vena cava is the largest vein

12. Blood Vessels Capillaries Smallest of blood vessels
Only one cell thick (epithelial cell)
Connect arteries to veins
Bring oxygen and nutrients to cells
Removes CO2, nd other wastes from cells
Where blood is under low pressure and moving slowly

13. Blood Pressure
Blood pressure refers to the force exerted by circulating blood on the walls of blood vessels
The pressure of the circulating blood decreases as blood moves through arteries, arterioles, capillaries, venules, and veins

14. Blood Pressure
Blood pressure is most commonly measured via a sphygmomanometer (blood pressure cuff)
Average blood pressure for an adult is 120/80

15. Pulse
A person's pulse is the throbbing of their arteries as an effect of the pressure waves (heart beat)
Pulse is used to denote the frequency of the heart beat
It can be felt at neck, wrist, and other places
Pulse is usually measured in beats per minute.
In most people, the pulse is an accurate measure of heart rate.

16. Blood
A circulating connective tissue consisting of several types of cells suspended in a fluid called plasma.

17. Blood Functions of blood: Supply oxygen Supply nutrients
Removal of wastes

18. Blood What percent of your body is blood? 8%
How much blood do we contain?
On average 4-6 liters
We contain about a pint of blood for every 15 pounds of body weight
Composition of Blood:
What percent of your blood is cellular?
What percent of your blood is plasma? 8%
45%
55%

19. Layering of blood components in a centrifuged blood sample
What is plasma?
A clear, straw colored fluid
What percent of plasma is water?
What’s in plasma?
Buffy coat leukocytes
and platelets
(<1% of whole blood)
Erythrocytes
(45% of whole blood)
Plasma
(55% of whole blood)
Formed
elements
90%
Dissolved gasses
Vitamins
Minerals
Salts
Nutrients
Layering of blood components in a centrifuged blood sample

20. Blood The cellular components are:
red blood cells
white blood cells
platelets
Blood cells are formed in bone marrow

21. Blood Red Blood Cell Characteristics Life span about 120 days
5 billion/1mL of blood = most numerous
Are very small

22. Blood White Blood Cell Characteristics Protect body against infection
Life span varies (3 days-a few months)
7,000/1mL of blood
Numbers increase if infection is present
Larger than red blood cells

23. Circulatory System Disorders
Heart Disease
Risk factors
Older age
Male
Cigarette smoking
High cholesterol
Diabetes
Stress
Obesity
Family history
Little to no exercise 
High blood pressure  
Quitting smoking, a healthy diet and exercise may
reduce your risk of heart disease
Plaque in
coronary
artery

24. Circulatory System Disorders
Atherosclerosis
Fatty deposits called plaque build up in the arteries
This causes:
Blockage in artery
Less flexible vessels
High Blood Pressure

25. Circulatory System Disorders
Hypertension
High Blood Pressure
Makes the heart and blood vessels work harder
Increases the chance of heart disease, heart attack or stroke

26. Circulatory System Disorders
Heart Attack
acute myocardial infarction
Interruption of oxygen supply to the heart
Causes death of the heart muscle
Leading cause of death in both men and women
Coronary Blockage

27. Circulatory System Disorders
Heart Attack
Symptoms
Chest pain
Squeezing or heavy pressure on chest
Pain that radiates down left shoulder and arm
Shortness of breath
Nausea or vomiting
Anxiety or Fainting
Lightheadedness - dizziness
Palpitations (feeling like your heart is beating too fast)
Sweating, which may be extreme

28. Circulatory System Disorders
Stroke
Interruption of oxygen supply to the brain
Caused by:
A clot in an artery in the brain
Breakage of an artery in the brain
Causes brain cells to be deprived of oxygen and die

29. Circulatory System Disorders
Hemorrhage
Hemorrhage is the medical term for bleeding - the loss of blood from the body
Hemorrhage generally becomes dangerous, or even fatal, when it causes low blood volume or low blood pressure.
Hematoma- a collection of blood due to internal bleeding
Gingival Hemorrhage

30. Circulatory System Disorders
Hem philia
A rare inherited bleeding disorder in which the blood does not clot normally
The person is missing or has low levels of certain proteins in the blood called clotting factors
Usually occurs only in males
They suffer prolonged bleeding even with minor injuries
Swelling in left knee joint due to spontaneous bleeding

31. Circulatory System Disorders
Anemia
Very few red blood cells
Body doesn’t get enough oxygen
Most common disorder of the red blood cells, affecting ~3.5 million Americans
A person with anemia will feel tired, weak, breathless, and dizzy
They may have a pale complexion, increased heart rate, low blood pressure, and difficulty concentrating
Severity changes