1. The Cardiovascular System Dale Embleton
THE BODY IN ACTION
The Cardiovascular System
Dale Embleton

2. The cardiovascular system
What you need to learn …
The structure of the cardiovascular system
The blood
The heart and valves
The blood vessels
The functions of the cardiovascular system
Heart contraction
Cardiac cycle
Pathway of blood

3. The cardiovascular system
The cardiovascular system consists of the heart, blood and blood vessels, and is also referred to as the circulatory system of the body.

4. The cardiovascular system
The circulatory system consists of three parts
The blood – in which materials are carried to and from the tissues
The heart – the muscular pump that pushes blood to the working muscles
The blood vessels (venules, veins, arteries, arterioles and capillaries) – the routes by which the blood travels to and through the tissues, and back to the heart

5. The cardiovascular system
Key points
Arteries carry oxygenated blood away from the heart
Veins carry de-oxygenated blood back to the heart
Capillaries connect veins and arteries

6. STRUCTURE

7. The cardiovascular system: BLOOD
Functions of blood
Carries nutrient substances absorbed from the intestine to the tissues
Carries oxygen to the tissues
Carries waste products from the tissues to the kidneys and liver
Returns carbon dioxide from the tissues to the lungs
Regulates body temperature
Distributes hormones and other agents
Fights bacterial infection through the white cells and antibodies

8. The cardiovascular system: BLOOD
A closer look at the structure of blood …
Plasma
Liquid
Erythrocytes
O2 and CO2
Leucocytes
Immune
Platelets
Blood clots
See Handout and complete worksheet 45

9. The cardiovascular system: HEART
The heart
Situated in the left-hand side of the chest
Muscular pump whose purpose is to drive the blood into and through the arteries, to deliver it to the tissues and working muscles
Considered as two separate pumps
Two chambers on the right, and two chambers on the left side
What are they?

10. The cardiovascular system: HEART
Structure of the Heart
Surrounded by sac known as the pericardium, which prevents friction as the heart beats.
Heart wall is made of:
Epicardium (outer layer)
Myocardium (strong middle layer)
Endocardium (inner layer)
Right separated from left by Septum

11. The cardiovascular system: HEART
The structure of the heart and blood vessels
Task
In pairs research and complete work sheets 42, 43 and 44

13. The cardiovascular system: HEART
The heart functions (continued)
Right atrium receives de-oxygenated blood from the body
Right ventricle pumps it to the lungs
Left atrium receives oxygenated blood from the lungs
Left ventricle pumps oxygenated blood to the body

14. The cardiovascular system: HEART
Circulation of Blood

15. The cardiovascular system: HEART
The heart valves
The heart has 4 valves
Choose 1
Using books/web, draw these valves
Identify their location
What is their function?
When will they open and close?
Present to the class

16. The Cardiovascular System: BLOOD VESSELS
Complicated network of blood vessels
96 kilometres of arteries, arterioles, capillaries, venules and veins.
Their structure relates to their function
Next two slides and handout have more information on the blood vessels
Page

17. The cardiovascular system: BLOOD VESSELS
SRUCTURE
3 groups
Explain the structure of these blood vessels using a diagram and labels

18. The cardiovascular system: BLOOD VESSELS
Main blood vessels and their functions
Aorta – Main artery of the body carrying oxygenated blood to the body tissues
Pulmonary artery – Carries deoxygenated blood from the lungs back to the heart
Superior vena cava – Receives deoxygenated blood from the upper body to empty into the right atrium of the heart
Inferior vena cava – Receives deoxygenated blood from the lower body to empty into the right atrium of the heart
See Handout for further information and complete worksheet 45

19. OF THE CARDIOVASCULAR SYSTEM
FUNCTIONS
OF THE CARDIOVASCULAR SYSTEM

20. THE HEART’S CONTRACTION
Contraction causes blood to move
The SA (sinoatrial) node is the pacemaker
Endocardial of right atrium
beats per minute
AV node (septal wall of right atria) slows impulse between the atria and ventricles to allow time for contracting atria to fill ventricles.
What would happen otherwise?

21. Using textbook handout, complete Worksheet 47,question 1 and 2
CARDIAC CYCLE
“The period from the beginning of one heart beat to the beginning of the next”
Two distinct phases
Systole
diastole
Using textbook handout, complete Worksheet 47,question 1 and 2

22. Cardiac output = rate at which blood leaves the heart
Stroke volume = volume of blood that leaves the heart with each beat
CO = SV X HR
Complete worksheet 47 and 48

23. Summarise these in a few sentences on your Handout
PATHWAY OF BLOOD
There are 3 modes of circulation that transports blood through the body.
Pulmonary
Systemic
Coronary
Summarise these in a few sentences on your Handout
Now complete worksheets 46

24. PATHWAY OF BLOOD…cont….
Blood Pressure
The blood is always under pressure
Without it where would the blood in your body be?
It therefore enables the blood to gravitate upwards in the body and through capillaries.
Worksheet 49

25. Where can you find a pulse? Why? What is it a measure of?
THE PULSE
Where can you find a pulse?
Why?
What is it a measure of?
Healthy adults = ______ - _______ bpm

26. Blood may pool in your cardiovascular system
BLOOD POOLING
This is where blood is not returned to the heart and lungs for re-oxygenation.
Fainting may occur………
Why?......what has this got to do with gravity?
Blood may pool in your cardiovascular system
Low blood pressure
Terminating activity without a recovery phase.

27. The cardiovascular system
What you need to learn …
The structure of the cardiovascular system
The blood
The heart and valves
The blood vessels
The functions of the cardiovascular system
Heart contraction
Cardiac cycle
Pathway of blood