Transcript Oxygen - Noadswood Science

How does oxygen
get around your
body?
L/O ;- To know the pathway of oxygen
through the circulatory system
Is blood
ever
blue?
Human blood is never blue
but some animals e.g. the
horseshoe crab have copper
in their blood instead of iron
which makes it blue instead
of iron
What is the job of
the circulatory
system?
What organs do you
think are in the
circulatory system?
The circulatory system
consists of the heart,
arteries, veins and capillaries
Circulatory System
Oxygen
• Oxygen is initially absorbed into the blood
within the lungs (via diffusion)
• It will now travel through a variety of
systems in order to get to the cell, where it is
needed for…
RESPIRATION!
Traveling
• Blood travels through three types of vessel - arteries, veins and
capillaries with have specific properties: – Arteries are thick-walled muscular tubes which carry blood
away from the heart - fast flowing!
– Veins are thin walled tubes which carry blood back to the
heart – they have a large diameter and valves as the blood
flows slower
– Capillaries are extremely narrow tubes which carry blood
through our tissues: their walls are just one cell thick - so
thin that oxygen, food and waste products can easily pass
through them
Blood
• Blood is a liquid tissue whose function is to fight
disease and to transport materials around the body
•
•
•
•
Blood plasma (liquid) containing glucose, amino acids, nutrients, hormones, as well as waste materials like urea
Red blood cells contain haemoglobin, a protein which picks up oxygen molecules in the lungs
White blood cells fight disease by making antibodies and fighting germs
Platelets are cell fragments. Together with fibrinogen they form clots to repair cuts or tears in nearby tissue
Heart
• What do you know about our heart? How does it
work? How is it specialised?
• The heart pumps blood around the body – in humans
this is a four chambered pump
• The right side of the heart pumps
deoxygenated blood to the lungs to
pick up oxygen
• The left side of the heart pumps
the oxygenated blood from the
lungs around the rest of the body
(which is why it is more muscular)
Heart
• The right side of the heart pumps deoxygenated blood to the
lungs to pick up oxygen
• The left side of the heart pumps the oxygenated blood from
the lungs around the rest of the body (which is why it is more
muscular)
Cells
• Oxygen and glucose leak out of the capillaries and the
cells close by absorb the required oxygen and glucose
• The waste products (including carbon dioxide) pass
out of the cells and into this fluid, that is then reabsorbed by the blood
• Capillaries do not join up to every cell - instead fluid
is passed out of them, with cells close by absorbing
what they need
Summary
• Oxygen enters the body in the lungs, via breathing
• It is absorbed into the blood, where it passes through
the heart and then throughout the body (via the
circulatory system)
• It travels through arteries, veins and capillaries
• Cells and blood exchange materials in the fluid, which
is released adjacent to the capillaries
• The cells then use this oxygen for respiration
Worksheet
• Match the circulatory key
words with their function
• Complete the circulatory
system worksheet
Arteries
Heart
Veins
Capillaries
One cell thick