Transcript Circle of Life

B3 resources
Here’s a typical animal cell
What are the main substances needed by the cell?
What are its main waste products?
Which vital process inside the cell requires food (glucose) and oxygen?
glucose + oxygen
_________ + __________ +
How do the substances move in and out of cells?
Here’s an animal cell surrounded by a liquid.
The strength of the tint shows the
concentration of oxygen
?
?
Which way will the oxygen molecules travel?
What is this process called?
Click to reveal answer
Answer
Answer
The oxygen molecules will move into the cell by diffusion.
They move from a high concentration of oxygen to a low
concentration of oxygen
down a concentration gradient.
What happens when the animal is bigger and made of many cells?
How easy is it for the cell in the centre to get oxygen?
Choose the length of the side of the animals by clicking on the red
buttons below. Then work out their surface area to volume ratios.
The first one has been done for you!
1
2
3
Length of side
1
2
3
4
5
5
4
Surface area of
‘animal’ (sq.units)
Volume of ‘animal’
(cubic units)
Surface area to
volume ratio
6
1
6:1
You can see from your results that as the ‘animal’ gets bigger, the
surface area gets relatively smaller compared with the volume.
This has massive implications for animals, especially how they get
sufficient oxygen and food to all of their cells.
The next few slides show you some examples ...
This is a uni-cellular organism (made of one cell)
called a Paramecium
How does it get its food and oxygen?
How does it get rid of waste?
By Giuseppe Vago
Here’s a clue!
By Giuseppe Vago
The substances move in and out of the animal by
diffusion. There is no need for a circulatory system.
Why not?
oxygen / food
Carbon dioxide / waste materials
By Giuseppe Vago
This is another simple animal
called a Tube Sponge
How does it get its food
and oxygen?
How does it get rid of
waste?
By aa7ae
Here are a few clues ...
By aa7ae
carbon dioxide / waste materials
food / oxygen
By aa7ae
Substances diffuse in and out of the
sponge’s cells as the water passes through.
There is no need for a circulatory system.
Why not?
How does an Earthworm get its food and oxygen?
How does it get rid of waste?
By Schizoform
Here are a few clues ...
By Schizoform
oxygen
waste materials
Food
carbon dioxide
By Schizoform
Earthworms do have a simple circulatory system. They have blood
vessels and five simple ‘hearts’.
Why does an earthworm need this whereas a larger sponge does not?
Complete this chart to remind yourself about how animals of
increasing complexity get food and oxygen to their cells
Animal
Paramecium
Sponge
Earthworm
Me
(a human!)
How they get
food
How they get Do they have a
oxygen
circulatory system?
Why? / Why not?
How they get rid of
waste
Use the BBC Bitesize website (or other resources) to learn
more about the human circulatory system.
Follow this link to see an animation about the different types of blood
vessels ...
... then complete this chart to record the differences between the three
types.
Type of blood
vessel
Thickness of
walls
Pressure of
blood inside
blood vessel
Any other
features?
Why?
Where they
carry blood
from/to
Click here for an animation on the BBC Bitesize website
which explains how the blood circulates through the heart
and around the body
Listen out for the names of the different parts of the heart and
the blood vessels which carry the blood in and out of the different
chambers
On the next slide you will need to arrange the parts in
the correct order...
... then shade the blocks with the correct colour to
indicate oxygenated or deoxygenated blood.
8
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
7
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
9
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
10
6
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
5
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
4
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
Starting from the kidney keep
clicking on each box until you
have sorted all the parts in
the correct order as the blood
circulates around the body
and back to the kidney.
3
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
2
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
1
Then, click on the
coloured spots in
each box to show if
the blood is
oxygenated (red), or
deoxygenated (blue)
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
11
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
12
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
13
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
14
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
15
Pulmonary
Left
Right
Renal
Left
Vena
Aorta
Valve
ventricle
atrium
atrium
artery
cava
arteries
Pulmonary
Right
Renal
Lungs
ventricle
vein
veins
Show
solution
Lungs
Pulmonary arteries
Valve
Pulmonary veins
Left atrium
Right ventricle
Valve
Left ventricle
Valve
Valve
Right atrium
Vena cava
Renal vein
Aorta
Renal artery
Back
You will have noticed that as the blood goes once around the body, it goes through
the heart twice. Once through the right side which pumps blood to the lungs, and
once through the left side which pumps blood to the other organs of the body.
This is called ‘double circulation’
You may have heard of a medical condition known as ‘Hole in the heart’,
where the double circulation doesn’t quite work properly
Work in a group to find out about this
condition using a ‘Post-it Challenge’
type of thinking activity
(You can even do this on-line using one
of several web-sites.
See guidance notes for details)
Focus on capillaries...microscopic but vital!
Here are a few statements about capillaries in the human body.
Are they true or false? Click on T/F to make your choice.
1.
Networks of capillaries are found in every organ of the body
2.
Every cell in the body has a capillary within 0.05 mm of it
3.
The walls of capillaries are only one cell thick
4.
The largest capillaries are just 0.2mm wide (thinner than a
hair)
5.
Water, oxygen, carbon dioxide and glucose molecules can
pass through the walls of capillaries
6.
White blood cells can pass through the walls of some
capillaries
Reset
Answer
You can think of the capillary
network as a vital part of a
transport system, dropping off
the substances required and
collecting up and removing
unwanted substances
By BidbyGraham
By Zero
By Daquella Manera
Here’s a magnified diagram of a capillary network showing how
closely it is linked with the surrounding cells
Blood coming
from an artery
Blood going to a vein
Substances passing
(diffusing) between
capillaries and cells
Use your understanding of what happens in capillary networks to try
the activities on the next few slides ...
Activity 1. Here is a magnified part of a capillary network in a tissue of the
human body (such as skin or muscle)
A
blood
from
B
blood
going to
Label the arrows by dragging the boxes below to the correct places.
Carbon Dioxide
Oxygen
Glucose
An artery
A vein
Waste substances
Think about where the concentration of each of the substances would be higher.
At A or B ?
Answer
Back
Activity 2. Here is a magnified part of a human lung showing the capillaries
wrapped around an air sac (alveolus)
Blood from the
A
which has been
pumped from the
right ventricle
Blood going to the
B
then entering the
left atrium of the
heart
Label the arrows by dragging the boxes below to the correct places.
oxygen
waste substances
air in
carbon dioxide
pulmonary artery
pulmonary vein
glucose
air out
Think about where the concentration of each of the 4 substances would be higher.
At A or B ?
Answer
Back
Activity 3. Here is a part of a capillary knot inside a Bowman’s capsule in a
human kidney
Blood coming from
A
B
Blood going to rest of
nephron (kidney
tubule) eventually
joining to form the
Label the arrows by dragging the boxes below to the correct places.
renal artery
oxygen
renal vein
glucose
water
carbon dioxide
mineral salts
Think about where the concentration of each of the 5 substances would be higher.
At A or B?
Answer
Back
What did William Harvey discover?
The structure of the human circulatory system and the way the blood
circulates around the body may now seem obvious to you, but back in the
17th century there were some very different ideas!
Use a KWL grid (next slide) to help you
investigate how William Harvey worked
out how the blood circulates around
the body.
These days medical researchers are
keen to talk about their work, presenting
their findings at international
conferences and on the internet.
Image courtesy of Wellcome Library, London
William Harvey was reluctant to report
his ideas at the time. Why might this
have been?
KWL grid
(Know – Want to know – Learned )
How did William Harvey find out about the circulatory system?
K
W
L
What do I know?
What do I want to
know?
What have I learned?
Write in this box
Write in this box
Write in this box
Check out your understanding of the circulatory system by extending this spider chart
unicellular
animals
invertebrates
The circulatory
system....
why and what...
blood
vessels
human
circulatory
system
4 chambers
heart
valves
blood supply to
heart muscle
cells