Transcript Notes on Circulation

The Circulatory System
•Carries needed substances to cells and waste products away.
•Links all parts of the body (highway system)
•Helps maintain balance (regulates body temperature and pH)
•Contain cells that fight disease.
HEART
•Muscular pump
(makes force to
push blood)
•Consists of an
upper chamber
(atria) and lower
chamber (ventricle)
•The atria collects
blood and the
ventricles pump the
blood
RA
LA
LV
RV
DOB
OB
VALVES
Flap-like
structures
that
prevent
backflow
of blood
BLOOD VESSELS
Serves as a pathway for blood
flow
to
ARTERIES
• Carries blood away from
the heart
• Oxygenated blood (OB)
• Thick-walled vessels
ADAM Animation: Coronary artery disease
VEINS
• Returns blood to the heart
• Deoxygenated blood (DOB)
• Thin-walled vessels with
valves to prevent backflow of
blood
ADAM animation- Blood Flow
CAPILLARIES
CAPILLARIES
• One-celled vessels
• Site of material exchange
• Contains tissue fluids
• Connects to venules and
arterioles
ADAM animation- Nutrient exchange
Blood Vessels
Arteries
Thick
muscular
wall
Small
lumen
(hole)
Oxygenated Blood
Except pulmonary
artery
Capillaries
Thin wall
(1 cell thick)
Veins
Thin
floppy
wall
Very
Small
lumen
O2  CO2
Large
lumen
(hole)
Deoxygenated Blood
Except pulmonary
vein
Blood Vessels
Arteries
High Pressure
Fast moving
Capillaries
Veins
Low Pressure
Very slow
Low Pressure
Slow moving
Small lumen to
maintain high
pressure
1 cell thick lumen
for exchange of
gas
Large lumen so
less resistance to
flow of blood
No valves , blood
is at high pressure
No valves
Valves to prevent
back flow
Pulse
No pulse
No pulse
BLOOD
River of life
Consists of red
cells, white cells and platelets
floating in a liquid called plasma
PLASMA
Liquid part of the blood
Consists of water and dissolved
substances
 ions ,proteins,food substances
Hormones,Excretory product, Urea
FACTS
5–6 liters of blood in the
body of an adult
each cubic centimeter
contains about 5 billion
red blood cells
RED BLOOD CELLS
tiny,disc-like cells; no nuclei
contains red pigment
Hemoglobin (carries oxygen)
Blood
Component Structure
Red Blood Cell
(RBC)
Function
O2 transport from
lungs to all cells
Biconcave disc
No nucleus
Contains
haemoglobin
(red)
WHITE BLOOD CELLS
• larger cells with
nucleus
• 1 WBC per 600
RBC
• act as soldiers of
the body; to fight
infections
Blood
Component Structure
White Blood Cell
(WBC)
Lobed nucleus
Function
Fight infection
Engulf bacteria
(swallowing)
Phagocytes
Lymphocytes
Large nucleus
Antibodies
(chemicals that
destroy bacteria)
PLATELETS
•Promotes blood
clotting
•Prevent bleeding
clotting
Blood
Component Structure
Function
Platelets
Cell fragments
(broken pieces
of cells)
Blood clotting
Plasma
90% water
10% dissolved
substances
e.g. glucose,
CO2 , enzymes,
hormones,
antibodies
Transport
Yellow / straw
coloured
Double Circulatory System
CO2
O2
Lungs
Pulmonary Artery
Pulmonary Vein
CO2
O2
Vena Cava
(main vein)
Aorta
(main artery)
Heart
Arteries carry blood
Away from the heart
CO2
O2
Rest of body
Veins carry blood
towards the heart