Energy released depends on conditions under which the chemical
changes take place.
Respiration
Anaerobic
Glucose = lactic acid (+energy available for cells to use
Aerobic
Glucose + Oxygen = carbon dioxide + water (+ energy available for cells to use)
Energy is made available for cells
to use in the form of ATP (adenosine triphosphate)
KEY DEFINITION: A molecule of ATP is formed when three
phosphate groups are attached to an adenosine molecule.
Energy is required to attach the phosphates (esp. the 3rd).
Respiration provides this energy. ATP is produced during
respiration and when the ATP is broken down (ATP to ADP) the
energy is released. ATP is used as a means to transfer energy
from one process to another.
Glucose
Comes from food eaten
Oxygen
Comes from air breathed in
The circulatory system and the respiratory systems work together
Biochemical changes for anaerobic
respiration takes place in the cytoplasm
where there are enzymes that promote
these reactions.
Biochemical changes for aerobic
respiration take place in the mitochondria
Most respiring cells in the body are away from the gut/lungs
Wastes have to be excreted
The circulatory system delivers oxygen to
respiring cells and takes carbon dioxide
away from the cell to be released in the
lungs
Also transports the energy
released as heat or in chemical
form to parts of the body that
need it
Why is respiration so important?
MRS NERG - Growth, sensitivity,
nutrition, movement, excretion
and reproduction all require
energy to make chemical
changes.
Respiration
provides energy in
the form of ATP
Breaks down into ADP and in turn AMP
(adenosine monophosphate), so that the phosphate groups
may be transferred to other molecules to make
them more reactive and making chemical change more likely.
Example, ATP provides energy for
chemical change in the eye retina
making visual pigments.
One form of AMP is a messenger in
the body. Cyclic AMP activates
enzymes to make chemical changes
more likely.
Hormone triggers the production
of cyclic AMP which activates the
enzymes associated with that
hormone. As a result hormones
control changes that happen in
the body.
Energy for:
Muscle
-contraction,
-nerve impulse
-transmission,
-separation of
chromosomes in
nuclear divison,
-active transport
and uptake of ions