Download Analysing adaptations for respiration

Analysing adaptations for respiration
Aseel Samaro
 They are both structures that transfer energy from type to another.
 Mitochondria provides energy for our cells.
 The power station provides energy for our homes.
 The mitochondria in our cells act as a surface for respiration to take
place
 Both mitochondria and power station produce carbon dioxide in the
process
Analysing adaptations for respiration
 Cells contain several structures, each with a
specific function – these are called organelles.
 An example is the mitochondrion.
 Mitochondria are described as ‘powerhouses’. This
is because they are the site of respiration, the
process by which energy is released.
 The numbers vary in different cells depending on
how much energy each cell needs.
Respiration powerhouses
 Mitochondria are tiny sausage-shaped organelles found in
most animal and plant cells.
 You can use a powerful microscope (such as an electron
microscope) to see their complex structure.
 Each mitochondrion has two membranes.
 The outer membrane surrounds the entire organelle.
 The inner one is highly folded – the tips of the folds
are called ‘cristae’.
 Respiration takes place on the cristae.
 Folding increases the number of cristae, maximising
the amount of respiration that can take place.
 The fluid inside the mitochondrion is called the matrix.
It contains the enzymes essential for respiration.
Describe where mitochondria are found.
Explain why mitochondria are called ‘powerhouses’.
Explain how folding of the inner membrane helps mitochondria to
produce more energy.
Counting mitochondria
The numbers of mitochondria vary in different types of cell.
Type of cell
Average number of mitochondria per
cell
muscle cell
1900
red blood cell
0
liver cell
1300
skin cell
800
mucus cell
180
Why do muscle cells need lots of mitochondria?
Mitochondria can make copies of themselves if more
are needed in a cell. Suggest when a cell may need
more mitochondria.
What can go wrong?
 If mitochondria do not function properly, then cells do not get the
energy that they need.
 When mitochondrial disease occurs, little or no respiration takes place
in the mitochondria.
 The organs most affected are those needing most energy such as the
heart (and other muscles), liver and brain.
 The symptoms are variable, depending on which mitochondria are
affected.
 Mitochondrial disease is caused by a fault in inherited material.
Suggest why sufferers of mitochondrial disease are often exhausted.
Explain why it is wrong to think that we can ‘catch’ mitochondrial
disease.
Explain why the most severe symptoms may be seen when
mitochondria in the brain are affected.
Did you know…?
 Some scientists believe that mitochondria are descended from
bacteria.
 They think that bacteria similar to mitochondria once existed in
their own right.
 These bacteria are thought to have entered cells.
 Over time, they evolved to exist within the cells and develop into
mitochondria as we see them today.
Thank you