Life Sciences Grade 11

1. TRANSPORT
SYSTEMS IN
ANIMALS

2. Welcome to the new chapter on
Transport Systems in Animals!
This is a super fun unit especially because
you can relate to all the topics to be
discussed.
You are going to learn so much about your
own body!
Lets dive straight in!
Ready, set, go!!
ALL THE PICS OF Ms P WILL HAVE
LINKS TO VIDEOS OR SUPPORTIVE
MATERIAL
Click me

4. FUNCTIONS OF ARTERIES
• Arteries: transports oxygenated
(O2) blood except for pulmonary
artery.
• Main artery  Aorta  pumping
oxygenated blood AWAY from
heart  rest of body.
• Other arteries:
• Renal artery (kidney)
• Hepatic artery (liver)

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

7. FUNCTIONS OF CAPILLARIES
Capillaries: Connect arteries & veins
structurally suited  exchange of
substances between blood in
capillaries & interstitial tissue fluid
(between cells)

8. DIFFERENT BLOOD VESSELS:
ARTERIES, VEINS AND CAPILLARIES

9. THE HUMAN CIRCULATORY SYSTEM:
HEART AND ASSOCIATED VESSELS

10. DOUBLE CIRCULATION
• Circulatory systems  2 distinct
circuits.
• The pumps of the 2 circuits serve
different tissues but combined into
single organ, the heart.
• The 2 circuits are called:
1. Pulmonary circuit
2. Systemic circuit

11. DOUBLE CIRCULATION
1. Pulmonary circuit
Heart pumps deoxygenated (CO2) blood to
lungs & oxygenated (O2) blood back to
heart.
2. Systemic circuit
Heart pumps oxygenated (O2) blood to
body cells & deoxygenated (CO2) blood
back to heart.

12. DOUBLE CIRCULATION

13. BLOOD VESSELS  TRANSPORT
GAS, NUTRIENTS & WASTE
PRODUCTS THROUGH BODY

14. THE HUMAN CIRCULATORY SYSTEM:
HEART AND ASSOCIATED VESSELS
 Mammals have 4-chambered heart with 2 atria &
2 ventricles
 Left side of heart pumps & receives only oxygen-
rich blood,
 Right side receives & 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.

15.  Blood then flows from right atrium into right
ventricle through tricuspid valve
 The blood is then pumped into lungs, through
semilunar valve via pulmonary artery.
 In lungs, blood loads O2 and unloads CO2.
 Oxygen-rich blood from lungs enters heart via 4 x
pulmonary vein at left atrium
 Blood then flows into left ventricle through
bicuspid valve.
 This blood is then pumped through semilunar
valve into aorta with takes blood to entire body.

16.  Deoxygenated blood returns to heart through
superior vena cava (blood from head, neck,
forelimbs) & inferior vena cava (blood from
trunk & hind limbs)
 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.

18. THE EXTERNAL STRUCTURE:HUMAN
HEART

19. THE INTERNAL STRUCTURE:HUMAN HEART

20. BLOOD FLOW THROUGH THE HEART
RED: OXYGENATED BLOOD -
BLUE: DEOXYGENATED BLOOD

21. CIRCULATORY SYSTEMS IN ANIMALS
 Many invertebrates do not have a
circulatory system at all.
 diffusion.
 E.G. Hydra

22. CIRCULATORY SYSTEMS IN ANIMALS
• In animals with multiple layers of cells
- cells are too far from external
environment for simple osmosis/
diffusion.
• Higher animals - 2 primary types of
circulatory systems - open & closed.

23. CIRCULATORY SYSTEMS IN ANIMALS
OPEN-
• The circulatory fluid – Hemolymph (is same as
interstitial tissue fluid)
• heart pumps hemolymph through vessels
into sinuses (open fluid-filled spaces)
• Certain substances are exchanged between
hemolymph and cells.
• Hemolymph returns to heart through pores.
• The heart is a tubular structure.

24. CIRCULATORY SYSTEMS IN ANIMALS
OPEN-

25. CIRCULATORY SYSTEMS IN ANIMALS
CLOSED-
• Circulate blood entirely within
vessels.
• Blood is distinct from interstitial fluid.
• Chemical exchange occurs between
blood & interstitial fluid & between
interstitial fluid & body cells.

26. CIRCULATORY SYSTEMS IN ANIMALS
CLOSED-

27. CARDIAC CYCLE
 The heart contracts and relaxes in a
rhythmic cycle called the cardiac
cycle
 The contraction / pumping, 
systole
 The relaxation / filling  diastole
 The heart rate  pulse (number of
beats per minute

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

29. MAINTAINING THE HEART’S RHYTHMIC
BEAT
 Some cardiac muscle cells are self-excitable, 
contract without any signal from nervous system
 The sinoatrial (SA) node (pacemaker, sets rate &
timing at which cardiac muscle cells contract
 Impulses from SA node travel to atrioventricular
(AV) node
 At AV node, impulses are delayed & then travel to
Purkinje fibres that make ventricles contract

30. MAINTAINING THE HEART’S RHYTHMIC
BEAT
Fig. 42-9-5
Signals spread
throughout
ventricles.
4
Purkinje
fibers
Pacemaker
generates wave of
signals to contract.
1
SA node
(pacemaker)
ECG
Signals are
delayed at
AV node.
2
AV
node
Signals pass
to heart apex.
3
Bundle
branches Heart
apex

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

32. LYMPHATIC SYSTEM VS. CIRCULATORY -

33. 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.

34.  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