gaseous exchange Flashcards
what do green plants trap during photosynthesis and what does it manufacture
they trap light energy and manufacture organic compounds
why cant animals and humans make use of energy directly from the sun
they do not have chlorophyll to trap the radiant energy
how do animals and humans get their energy
by eating plants and animals that in turn may have eaten plants in this way light energy is transferred from the sun to all living organisms
what do humans and animals have to do with the energy they obtained from the food they eat
they need to find some way of releasing the energy that is locked in the food they have eaten and digested
what do we require energy for
for various things we do such as walking running and growth
cellular respiration
the process by which energy is released
what do we require for cellular respiration to take place
we require oxygen
why is oxygen necessary
without oxygen we will not be able to make use of the energy that is within the food we eat
where does oxygen move in the body
from the lungs into the blood and from here into the cells, carbon dioxide moves in the opposite direction (gas exchange)
importance of gas exchange
it ensures that the oxygen from the air in the atmosphere or the air that is drawn into the body of an organism is able to pass through to the cells that require them for cellular respiration
what is the by product of cellular respiration
carbon dioxide
why cant carbon dioxide be allowed to accumulate in the body of an organism
it is toxic to the organism .if it would combine with water to form carbonic acid which reduces the pH
what will happen if the pH is reduced
it will affect the action of the enzymes which are sensitive to changes in pH
second importance of gas exchange
it helps to bring the carbon dioxide to the surface of the organism so that it can be eliminated
what does air passages consist of
the nostrils nasal passages the trachea bronchi bronchioles make up the air passages
