Cardiovascular system

1. Cardiovascular System
(Circulatory System)
This presentation is to supplement the reading of
the ‘Cardiovascular System’ in your anatomy book

2. The Closed Circulatory System
•The heart pumps blood into large blood vessels
that branch into smaller ones, leading into the organs.
•Materials are exchanged by diffusion between the
blood and the interstitial fluid bathing the cells.

3. Septum
Superior
Vena Cava
Inferior
Vena Cava
Aorta
Pulmonary
Veins
Pulmonary
Arteries

4. •Pulmonary circuit
•The blood pathway
between the right side of
the heart, to the lungs, and
back to the left side of the
heart.
•Systemic circuit
•The pathway between the
left and right side of the
heart via all the organs and
limbs of the body.

5. BloodVessels - A network of tubes
•Arteriesarterioles move away from the heart.
•Thick Smooth Muscle Wall
•Small Lumen(Internal area blood can flow through)
•VeinsVenules moves towards the heart.
•When Skeletal Muscles contracts they force blood
back from legs and other parts of the body.
•One way values
•Thin Smooth Muscle Wall
•Large Lumen
•Capillaries – where gas exchange takes place.
•One cell thick
•Smallest of the blood vessels.

7. The Blood
There are 4 main blood groups/types. A, B, AB
and O.Your blood group is determined by the
genes you inherit from your parents.
A blood group/type is a classification of blood,
based on the presence and absence of antibodies
and inherited antigenic substances on the surface
of red blood cells.
These antigens may be proteins, carbohydrates,
glycoproteins, or glycolipids, depending on the
blood group
Average human has 4 -5 liters of blood

8. The Blood Cells
Plasma (55% of Blood)
Liquid portion of the blood.
90%-92% Water
Contains clotting factors, hormones,
antibodies, dissolved gases, nutrients,
proteins and waste.

9. Plasma
A straw-
coloured
liquid that
carries the
cells and the
platelets
which help
blood clot.
• carbon dioxide
• glucose
• amino acids
• proteins
• minerals
• vitamins
• hormones
• waste materials
like urea.
It also contains

10. The Blood Cells
Erythrocytes, also known as
Red Blood Cells
•Carry hemoglobin and
oxygen.
Hemoglobin and oxygen,
when combined forms
oxyhemoglain and gives
blood it’s bright red colour
•Do not have a nucleus and
live only about 120 days.
•Can not repair themselves.

11. The Blood Cells
Leukocytes, also known as White Blood Cells
These cells fight infection and are formed in the bone
marrow
There are 5 types.
neutrophils, lymphocytes,
eosinophils, basophils,
and monocytes.

12. The Blood Cells
Thrombocytes
Also known as Platelets.
These are formed in the bone marrow .
Clot Blood by sticking together – via protein
fibers called fibrin.

13. Functions of the Heart
• Generating blood pressure
• Routing blood
Heart separates pulmonary and systemic circulations
• Ensuring one-way blood flow
Heart valves ensure one-way flow
• Regulating blood supply
Changes in contraction rate and force match blood delivery
to changing metabolic needs

14. Size, Shape, Location of the Heart
•Size of a closed fist
•Shape
Apex: Blunt rounded
point of cone
Base: Flat part at
opposite of end of cone
•Located in thoracic
cavity

15. The Heart Wall Is Made Up OfThree Layers Of Tissue
Epicardium / Pericardium:This serous
membrane of smooth outer surface of
heart
Myocardium: Middle layer composed of
cardiac muscle cell and responsibility for
heart contracting
Endocardium: Smooth inner surface of
heart chambers

16. Heart Wall

17. Coronary Circulation

18. HeartValves
(Bicuspid)

19. Blood FlowThrough Heart

20. Conducting System of Heart

21. Regulation of the Heart
Parasympathetic stimulation
(Covered in more detail in the NervousSystem)
• Supplied by vagus nerve & decreases heart
rate
Sympathetic stimulation
(Covered in more detail in the Nervous System)
• Supplied by cardiac nerves and increases heart
rate and force of contraction.

22. Cardiac Cycle
• Heart is two pumps that work together, right
and left half
• Repetitive contraction (systole) and relaxation
(diastole) of heart chambers
• Blood moves through circulatory system from
areas of higher to lower pressure.
Contraction of heart produces the pressure

23. Blood Pressure
Made up of two numbers:
Systolic blood pressure
(Higher Number)
Diastolic blood pressure
(Lower Number)
Ideal Level: 120/80

24. Systolic Blood Pressure
• Refers to the arterial pressure during the contraction
phase of the heart
• Corresponds with the onset of turbulent flow through
the arteries
• Average value is around 120 mmHg
(millimetres of mercury—the units used to measure blood pressure.)

25. Diastolic Blood Pressure
• Refers to the arterial pressure during the relaxation
phase of the heart
• Corresponds with the onset of laminar flow through
the arteries
• Average value is around 80 mmHg

26. Blood Pressure Must Be Regulated
Low Blood Pressure
Blood will not reach all
tissues
Specifically those where
gravity is acting against
flow
Most importantly the brain
High Blood Pressure
Heart is placed under great
stress
Excess plasma leakage
At the extreme, capillaries
burst

27. Cardiac Output & Exercise
Cardiac output must increase in exercise to meet the metabolic
demand of the active tissues.
Cardiac output(Q) is the amount of blood pumped around
the body in 1 minute
Q = HR x SV
Q is cardiac output (L/min)
HR is heart rate (beats/min)
SV is stroke volume (ml/beat)

28. Effects of Aging on the Heart
• Gradual changes in heart function, minor under
resting condition, more significant during
exercise
• Hypertrophy(Muscle Growth) of left ventricle
• Maximum heart rate decreases
• Increased tendency for valves to function
abnormally and arrhythmias to occur
• Increased oxygen consumption required to
pump same amount of blood

29. Disorders of the Circulatory System
• Anemia - lack of iron in the blood, low RBC count
• Leukemia - white blood cells proliferate wildly, causing anemia
• Hemophilia - bleeder’s disease, due to lack of fibrinogen in
thrombocytes
• Heart Murmur - abnormal heartbeat, caused by valve
problems
• Heart attack - blood vessels around the heart become blocked
with plaque, also called myocardial infarction