In this presentation I only focused on the human part of the circulatory system

1. TRANSPORT SYSTEMSIN HUMANS
By Gift Mokgotho

2. DOUBLECIRCULATION
• The circulatory systems with two distinct circuits.
• The pumps of the two circuits serve different
tissues but are combined into a single organ, the
heart.
• The two circuits are called:
1. Pulmonary circuit
2. Systemic circuit

3. DOUBLE CIRCULATION
1. Pulmonary circuit
The heart pumps deoxygenated blood to the lungs
and oxygenated blood back to the heart.
2. Systemic circuit
The heart pumps oxygenated blood to the body cells
and the deoxygenated blood back to the heart.

4. DOUBLE CIRCULATION

5. BLOOD VESSELS
3 Types:
a) ARTERIES
b)VEINS
c)CAPILLARIES

6. Arteries
• Transports oxygenated blood except for the
pulmonary artery.
• Main artery  Aorta  pumping oxygenated
blood away from heart  rest of body.
• Other arteries:
• Renal artery (kidney)
• Hepatic artery (liver)

7. Veins
• Transports deoxygenated blood except for
the pulmonary vein.
• Main vein is called the vena cava – pumping
deoxygenated blood towards the heart from
rest of the body.
• Other veins:
• Renal vein (kidney)
• Hepatic vein (liver)

8. Capillaries
• Connect arteries and veins
• They are structurally suited:
 exchange of substances between
the blood in the capillaries &
interstitial tissue fluid

9. STRUCTURE OF THE HEART

10. BLOODFLOWTHROUGH THE HEART

11.  Mammals have a 4-chambered heart with 2 atria & 2 ventricles
 The left side of the heart pumps & receives only oxygen-rich
blood,
 while the right side receives and pumps only
oxygen-poor blood
 The mammalian cardiovascular system meets the body’s
continuous demand for O2.
 Blood begins its flow when deoxygenated blood flow from the
body into the right atrium.
THE HEART AND ASSOCIATED VESSELS

12.  Blood then flows from the right atrium into the right
ventricle through the tricuspid valve
 The blood is then pumped into the lungs, through the semilunar
valve via the pulmonary artery.
 In the lungs, the blood loads O2 and unloads CO2.
 Oxygen-rich blood from the lungs enters the heart via the
pulmonary veins at the left atrium
 Blood then flows into the left ventricle through the
bicuspid valve.
 This blood is then pumped through semilunar valve into the
aorta with takes blood to the entire body.

13.  Deoxygenated blood returns to heart through
superior vena cava (blood from head, neck, and
forelimbs) & inferior vena cava (blood from trunk and
hind limbs)
 The superior vena cava & inferior vena cava flow into the
right atrium.
 The atrioventricular (AV) valves (tricuspid and
bicuspid valves) separate each atrium & ventricle
 The semilunar valves control blood flow to the aorta &
the pulmonary artery.

14. CARDIAC CYCLE
 The heart contracts and relaxes in a rhythmic cycle called
the cardiac cycle
 The contraction, or pumping, phase is called systole
 The relaxation, or filling, phase is called diastole
 The heart rate, also called the pulse, is the number of
beats per minute

15. CARDIAC CYCLE…
ARTRIAL DIASTOLE
ARTRIAL SYSTOLE
VENTRICULAR DIASTOLE
CARDIAC CYCLE
RED: OXYGENATED BLOOD -
BLUE: DEOXYGENATED BLOOD
VENTRICULAR SYSTOLE

16. THE HEART’S RHYTHMICBEAT
 Some cardiac muscle cells are self-excitable, meaning they
contract without any signal from the nervous system
 The sinoatrial (SA) node, or pacemaker, sets the rate and timing
at which cardiac muscle cells contract
 Impulses from the SA node travel to the atrioventricular (AV)
node
 At the AV node, the impulses are delayed and then travel to the
Purkinje fibres that make the ventricles contract

17. LYMPHATIC SYSTEM
 The lymphatic system returns fluid that leaks out in the capillary
beds
 This system aids in body defence
 Fluid, called lymph, re-enters the circulation directly at the
venous end of the capillary bed and indirectly through the
lymphatic system
 The lymphatic system drains into veins in the neck.
 Lymph nodes are organs that filter lymph and play an important
role in the body’s defence
 Edema is swelling caused by disruptions in the flow of lymph.

18. LYMPHATIC SYSTEM

19. DISEASES OF THE HEART AND CIRCULATORY SYSTEM
 Cardiovascular diseases are disorders of the heart and
the blood vessels
 They account for more than half the deaths in the South
Africa
 One type of cardiovascular disease, atherosclerosis, is
caused by the build-up of plaque (fat) deposits within
arteries.

20.  A heart attack is the death of cardiac muscle tissue resulting
from blockage of one or more coronary arteries
 A stroke is the death of nervous tissue in the brain, usually
resulting from rupture or blockage of arteries in the head.
 Hypertension, or high blood pressure, promotes atherosclerosis
and increases the risk of heart attack and stroke.
 Hypertension can be reduced by dietary changes, exercise,
and/or medication

21. Refrence
Kubesova, M. (2017). Transport systems in animals. Available from Slideshare at
Kuhn, T. (2011). The Circulatory System. Available from Slideshare at
Satnam, S. (2009). The Human Heart. Available from Slideshare at
https://www.slideshare.net/satnam8912/heart-slides
Shaji, S. (2015). Ks4 The Heart and Circulatory System. Available from Slideshare at
https://www.slideshare.net/SusanShaji/ks4-the-heart-and-circulatory-system-52481986
Yon, C. (2016). Human Anatomy: Heart. Available from Slideshare at
https://www.slideshare.net/Yon360/heart-53606150