The circulatory system transports blood throughout the body using the heart, blood vessels, and blood. Blood carries oxygen, nutrients, waste products, hormones, and more to tissues via the cardiovascular system which includes pulmonary and systemic circulation. The heart has four chambers and uses contraction to pump deoxygenated blood to the lungs and oxygenated blood throughout the body to meet metabolic demands.

1. Normal Heart Sound.mp3

2.  Discuss the need for transport system in multi-
cellular organisms.
 Describe the components of blood and their
functions
 Differentiate among blood vessels
 Describe the structure & function of the heart.

4.  The circulatory system is the transport system
found in mammals. Humans have a
cardiovascular system in which two types of
circulation occurs ( Systemic and Pulmonary)
 The circulatory system is composed
of three main parts:
 The heart
 The blood
 The blood vessels.

5.  Thisorgan pumps blood around the body at
different speeds and at different pressures
according to the body’s needs.
 The heart is made of CARDIAC MUSCLE.
 The cardiac muscles in the heart contracts and
relaxes continuously.

6.  This muscle has its own blood supply (coronary
circulation).
 Blood reaches the muscle via the coronary arteries.
 These carry blood to capillaries that supply the heart
muscle with oxygen & nutrients.
 This allows the heart muscle to keep on working.
 Blood returns to the atrium via coronary veins.

8.  The heart has four chambers:
 The two upper chambers are the Right and Left Atrium
 The two lower chambers are the Right and Left Ventricles.
 It’s
also divided into a right and left side by the
SEPTUM;
 The left side of the heart circulates oxygenated blood.
 The right side of the heart circulates deoxygenated blood.

9.  Blood enters the heart through the atria.
 Blood leaves the heart when the ventricles contract.
 The right ventricle pumps blood only to the lungs
 The left ventricle pumps blood to all parts of the body.
 This requires much more pressure, which is why the wall
of the left ventricle is much thicker than that of the
right ventricle.

10.  Deoxygenated blood from body enters from Vena
cava vein into RA
 Atria contracts and pushes blood from RA into RV
 Ventricles contract and blood is pushed into
pulmonary artery which goes towards the lungs.
 Gaseous exchange occurs at alveoli and pulmonary
vein brings back Oxygenated blood to LA.

11. This refers to a system that pumps blood to the
heart twice. It has two main parts:
 Pulmonary circulation: blood is first circulated
through the lungs where it is oxygenated.
 Systemic circulation: blood is then circulated
throughout the body where it unloads its oxygen,
and exchanged with deoxygenated blood.

14.  The blood is the medium
in which substances are
transported throughout
the body. It has many
other functions besides
transportation alone.

15. •The composition of materials transported by blood are:
Water
Gases (Oxygen, Carbon dioxide)
Salts
Nutrients
Nitrogenous waste products e.g. urea
Hormones & antibodies
Heat
•These substances that are transported are
dissolved in the blood plasma

16.  Blood is comprised
of
 Plasma
 Red blood cells
 White Blood cells
 Platelets

17.  Thisis the yellowish liquid part of blood,90%
is water
 Transports dissolved substances :
 Dissolved food
 CO2
 Hormones
 Mineral salts
 Nitrogenous waste

18.  The red blood cells are responsible for the
transport of oxygen
 It contains haemoglobin which combines
reversibly with oxygen (oxyhaemoglobin) and
is carried to cells.
 Oxygen is readily released from haem at
tissues where O2 level is low.

19.  These are the bodyguards against pathogen
infection
 They help fight against disease by
surrounding and destroying foreign objects
that are introduced into the system
 They are categorized according to their
actions
 Phagocytes: lobed nucleus, surrounds and
“eats” pathogen
 Lymphocytes: round nucleus, produce
antibodies which stick to and deactivates
pathogen.

20.  Plateletsare fragments of cells formed in
bone marrow
 They have no nucleus
 Function to help clot blood preventing blood
loss.
 What is the importance of clotting blood?
 Draw diagram of formation of blood clot.