Respiration is a chemical process in which energy is
released from food substances.
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Respiration is a series of actions in which energy is
released from glucose.
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Glucose – A sugar made by the body from food which
is used by cells to make energy in respiration.
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Cellular Respiration – Release of energy that happens
in our cells.
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Respiration:
glucose + oxygen – carbon dioxide + water + energy
transfer.
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Blood also carries the glucose needed for respiration. The glucose is
picked up by the blood vessels that surround our intestines. Glucose
is then carried to the cells and moves around the body, all the tissues
will get oxygen and glucose.
Blood is mainly water and so it is very good at dissolving things.
Waste dioxide is produced during respiration. This gas dissolves in
the plasma. The dissolved carried by the blood to the lungs where it is
released and breathed out.
Blood is needed to carry fuel, oxygen and waste materials around the
body. The fuel, glucose comes from food and the waste products,
carbon dioxide and water, are made in the cells. Blood is a sticky red
liquid that contains plasma and different types of blood cells. The red
blood cells carry oxygen. Glucose and carbon dioxide are dissolved in
the pale yellow liquid part of the blood, the plasma. Blood also carries
many other chemicals around the body.
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Arteries have thick walls and take blood away
from the heart. Veins have thinner walls and
take blood back to the heart. Capillaries are
tubes with very thin walls.
There are three main types of blood vessels,
arteries, veins and capillaries.
Blood flows from the arteries into capillaries
and the into veins.
The heart has two pumps that work together
one side pumps blood to the lungs, the other
side pumps blood to the rest of the body
Mitochondria are structures in cells where respiration
happens. Respiration is the process that releases energy
from glucose. This provides energy for life process such
as movement and growth.
Tissues and organs that need a lot of energy have large
numbers of mitochondria in their cells. For example,
liver cells and muscle cells contain a lot of
mitochondria.
Thin walls - to substances to pass
through easily.
Large surface cells – to allow
many reactions to make place at
once
What does respiration happen?
Respiration happens inside tiny structures inside your cells called
mitochondria. All cells contain mitochondria, but different cells contain
different amounts. Muscle cells carry out lots of respiration, so they contain
large amounts of mitochondria.
How does glucose get into cells?
Glucose is a carbohydrate found in food. Digestion breaks down food into
small molecules are absorbed by the wall of the same intestine, into the
blood by the wall of the small intestine, into the bloodstream. Glucose is
transported around your body in your blood. If dissolves in the liquid part
of your blood. If dissolves in the liquid part of your blood called plasma.
The dissolved glucose can diffuse into the cells that need it for respiration.
How does oxygen get into cells?
When you breathe in, oxygen fills the alveoli in your lungs. The
oxygen then diffuses into your bloodstream. Oxygen is carried by
the red blood cells in your body. Red blood cells contains
haemoglobin (the substance that makes them red). Oxygen joins
to the haemoglobin and gets carried around the body in the
blood vessels. When it reaches a cell requiring oxygen diffuses
into the cell.
How does carbon dioxide leaves the body?
If carbon dioxide remained in your body it would build up
to a harmful level. You get rid of carbon dioxide when you
exhale. Carbon dioxide produced during respiration diffuses
out of your cells and into the blood plasma. The blood
transports it to the lungs, where it diffuses into the air sacs,
and is then exhaled.
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Sports drinks contains glucose, chemical salts
and water.
We sweat when we exercise because our body
is trying to keep our temperature at night level.
Staying alive needs energy. Our main fuel,
petrol comes from the food we eat. In living
cells, energy is released when glucose reacts
with oxygen from the air we breathe. At the
same time water and carbon dioxide are
produced. This chemical reaction is called
respiration.
Aerobic respiration
Aerobic respiration requires oxygen. It happens in cells when
glucose reacts with oxygen.
Word equation for Aerobic respiration:
glucose + oxygen – carbon dioxide + water (+ energy)
Anaerobic respiration
Anaerobic respiration does not need oxygen. It happens
when there is not enough oxygen for anaerobic
respiration.
Word equation for Anaerobic respiration:
glucose – lactic acid (+ energy)
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Plasma- the pale yellow coloured liquid part of blood.
Red blood cells- the cells in the blood that carry oxygen.
Artery- thick walled tubes that carry blood away from the heart.
Capillary- very thin tubes that carry blood to the tissues of the
body.
Vein- thin walled tubes that carry blood back to the heart.
Lactic acid- A toxic chemical produced during anaerobic
respiration.
Oxidation- oxidation is a reaction in which oxygen combines with
a substance. Oxidation also means a loss of electrons.
Enzymes- a protein that speeds up chemical reactions.
The act of breathing is part of the respiratory
system is a process where air travels into and out
of the lungs. Respiration is different, where
exercise causes muscles to release energy in the
form of glucose.