CHAPTER 2 : BLOOD

CIRCULATION & TRANSPORT
2.1 : Transport
System in
Human
2.2 : Human blood
2.3 : Transport
System in Plants

Prepared  by  Ms  Sue  Soh  Ya  Lee  

2.1 : Transport System in Human
General Structure of the Human Heart
•  Human heart is located
inside the thoracic
cavity, behind the
breastbone & between
the left and right lung
•  Cone-shaped and tilts
slightly towards the left
side of our body
•  Has a mass of about 300g
& is built of thick and
strong cardiac muscles
•  Entire heart is covered
with a long lasting
membrane
•  The space between the
heart and the membrane
is filled with fluid to
reduce friction between
the heart and other
organs next to it Prepared  by  Ms  Sue  Soh  Ya  Lee  

1 : Transport System in Human Detailed Structure of the Human Heart •  There are four muscular chambers –  Left side : left atrium. left ventricle –  Right side : Right atrium. 2. right ventricle •  Septum separates the left and right chambers – WHY ? Prepared  by  Ms  Sue  Soh  Ya  Lee   .

1 : Transport System in Human Detailed Structure of the Human Heart VENTRICLES •  Has a larger volume of space than the atrium •  Has a thicker wall than the atrium •  Left ventricle is thicker and more muscular than the right ventricle – WHY ? Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

1 : Transport System in Human Detailed Structure of the Human Heart •  Each ventricle & atrium is linked to one big blood Pulmonary vessel artery v Left atrium – pulmonary vein v Right atrium – vena cava v Left ventricle – aorta v Right ventricle – pulmonary artery Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

1 : Transport System in Human Detailed Structure of the Human Heart •  The one-way flow of blood in the heart is controlled by three types of valves v Bicuspid valve (mitra valve) – controls blood from left atrium to left Semilunar ventricle valve v Tricuspid valve – controls blood from Bicuspid right atrium to right valve ventricle v Semilunar valve – controls blood from Semilunar valve ² left ventricle to Tricuspid aorta valve ² right ventricle to pulmonary artery Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

2.1 : Transport System in Human Functions of the Heart Functions as a strong muscular pump to collect :- •  Deoxygenated blood from the rest of the body – is pumped to the lungs •  Oxygenated blood from the lungs – is pumped throughout the body Prepared  by  Ms  Sue  Soh  Ya  Lee   .

urea & water) from the body cells to be removed from the body Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.1 : Transport System in Human Functions of the Heart Functions to circulate and transport :- •  Nutrients & oxygen to the body cells •  Excretory products (C02.

Superior   To  body   Aorta   Vena  cava   From   6 7 body   Pulmonary  artery   12 Semilunar  valve   11 To  le(  lung   Pulmonary   To  right  lung   1 veins   From  le(  lung   From  right  lung   Left  atrium   2 Pulmonary  veins   1 Bicuspid  valve   3 Right  atrium   8 Semilunar  valve   5 Tricuspid  valve   9 Left  ventricle   Inferior   6 4 vena  cava   Right  ventricle   10 From   body   Prepared   by  Ms  Sue  Soh  Ya  Lee   Septum   .

2.1 : Transport System in Human Pathway of Blood Circulation Vena Right Tricuspid Right cava Atrium valve ventricle Pulmonary Semilunar Lungs artery valve Pulmonary Left Bicuspid veins atrium valve Aorta Semilunar Left (Whole body) valve Prepared  by  Ms  Sue  Soh  Ya  Lee   ventricle .

1 : Transport System in Human Types of Blood Vessels •  Each blood vessel has lumen – the tract that allows blood to flow in the blood vessel •  Lumen is important because the size of lumen affects the blood flow in the blood vessels –  Narrow lumen will be an obstacle to the blood flow – blood flows faster & under high pressure –  Wide lumen provides less resistance to the blood flow – blood flows more slowly & under low pressure Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

1 : Transport System in Human Types of Blood Vessels •  There are 3 types of blood vessels : – Artery – Vein – Capillary •  As blood is pumped out of the heart. 2. veins and capillaries Prepared  by  Ms  Sue  Soh  Ya  Lee   . it travels through arteries.

1 : Transport System in Human Types of Blood Vessels ARTERY •  Carries blood out of the heart –  Aorta : artery that carries blood from left ventricle of the heart –  Pulmonary artery : artery that carries blood from the right ventricle to the lung •  Carries oxygenated blood except pulmonary artery •  Has narrow lumen Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

1 : Transport System in Human Types of Blood Vessels ARTERY •  The artery wall is thick. elastic and muscular to withstand high blood pressure •  Arteries don’t have valves except pulmonary artery and aorta •  Arteries which branch into smaller blood vessels are known as arterioles Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

2.1 : Transport System in Human Types of Blood Vessels VEIN •  The blood vessel that carries blood into the heart –  Vena cava : transports blood to the right atrium of the heart –  Pulmonary vein : transports blood from the lung to the left atrium •  Transport deoxygenated blood except pulmonary vein Prepared  by  Ms  Sue  Soh  Ya  Lee   .

1 : Transport System in Human Types of Blood Vessels VEIN •  Have wide lumen – blood flow is slow and under low pressure •  The wall is thin & less muscular •  Have semilunar valves to ensure one-way of blood flow •  Branch into smaller vessels called venules Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.

2.1 : Transport System in Human Types of Blood Vessels CAPILLARY •  Joins the artery to Artery   Capillary   the vein •  The narrowest blood vessel •  Carries a combination of oxygenated & deoxygenated blood •  Its wall is very fine : one-celled thick – enables the exchange of gases Vein   & nutrients between blood & body cells Prepared  by  Ms  Sue  Soh  Ya  Lee   .

1 : Transport System in Human Types of Blood Vessels CAPILLARY •  Blood flow is very slow and under low pressure so that exchange of substance can take place more efficiently •  Does not have any valves Prepared  by  Ms  Sue  Soh  Ya  Lee   .2.

2.1 : Transport System in Human The Human Blood Ciculatory System •  Heart is at the centre of the human circulatory system •  Blood circulation in the body happens due to the pumping action of our heart •  Human blood circulation is completed through 2 stages :- –  Pulmonary circulation –  Systemic circulation Prepared  by  Ms  Sue  Soh  Ya  Lee   .

1 : Transport System in Human The Human Blood Ciculatory System •  Both stages cause the blood to flow twice through the heart •  Complete pulmonary circulation is the to- and-fro circulation from the heart to the lung •  Pulmonary circulation alternates with the systemic circulation to complete the circulation around the body Prepared  by  Ms  Sue  Soh  Ya  Lee   . 2.