respiration and gas exchange Flashcards
(64 cards)
what is respiration
is the process of transferring energy from glucose, which happens constantly in every living cell
where is some of the energy transferred by in respiration
by heat
how does respiration work
Breathing in (Inhalation): You take in oxygen from the air through your nose or mouth, and it travels to your lungs.
Oxygen to Cells: Oxygen moves from your lungs into your blood, which carries it to your cells.
Energy Production:
Inside the cells, oxygen combines with glucose (from food) in tiny structures called mitochondria.
This process releases energy in the form of a molecule called ATP (adenosine triphosphate), which cells use for work.
Carbon dioxide and water are made as waste products.
Breathing out (Exhalation): Your body gets rid of carbon dioxide by breathing it out.
state –> the energy transferred by respiration cannot be used directly by cells - so it is used to make a substance called ATP, ATP stores the energy needed for many cell processes
when a cell needs energy, ATP molecules are broken down and energy is released.
what are the two types of respiration
aerobic
anaerobic
temp change in beans experiment
- soak some dried beans in water for a day or two. they will start to germinate. germinating beans will respire.
- boil a similar - sized, second bunch of dried beans. this will kill the beans and make sure they cannot respire. the dead beans will act as your control
- add each set of beans to a vacuum flask, making sure there is some air left in the flaks (so the beans can respire anaerobically )
- place a thermometer into each flask and seal the top with cotton wool
- record the temp of each flask daily for a week.
- repeats should be carried out using the same mass of beans each time
- the beans are well insulated in the flasks, so when the germinating beans respire, the test flask’s temp will increase compared to the control flask.
when does aerobic happen
when there is plenty of oxygen available
what does aerobic respiration mean
it means ‘with oxygen’ and it is the most efficient way to transfer energy from glucose. it produces lots of ATP - 32 molecules per molecule of glucose
what type of respiration are you using most of the time
aerobic
anaerobic respiration uses
NO OXYGEN AT ALL
what does anerobically oxygen mean
without oxygen, it is not the best way to convert glucose into energy - it releases much less energy per glucose molecule than aerobic respiration (just two molecules of ATP are produced
state –> in anaerobic respiration, the glucose is only partially broken down, and lactic acid is also produced
- the lactic acid builds up in the muscles and it gets painful and leads to cramps
word equation for anaerobic respiration
glucose –> lactic acid (+ energy)
anaerobic respiration in plants
- plants can respire without oxygen too, but they produce ethanol (alcohol) and CO2 instead of lactic acid
word equation for anaerobic respiration in plants
glucose –> ethanol + carbon dioxide (+ energy)
what can be used to show that living organisms produce CO2 as they respire
hydrogen carbonate indicator
what colour does the liquid change in the presence of carbon dioxide
the hydrogen carbonate indicator is orange but it changes to a yellow in the presence of carbon dioxide
investigating respiration
- prepare one set of germinating beans and one set of boiled beans
- put the same amount of hydrogen carbonate indicator into two test tubes.
- place a platform made of gauze into each test tube and place the beans on this.
- seal the test tubes with a rubber bung
- leave the apparatus for a set period of time (eg an hour)
during that time the CO2 produced by the germinating beans should have had an effect on the hydrogen carbonate indicator - it would have turned yellow
the control tube will have stayed the same
what do plants exchange
carbon dioxide and oxygen
what is the word equation for respiration
glucose + oxygen –> carbon dioxide + water (+ energy)
state –> when plants photosynthesise they use up CO2 from the atmosphere and produce O2 as a waste product
state –> when plants respire they use up O2 and produce CO2 as a waste product
how are these waste products lost
through little holes in the undersides of leaves called stomata
how do plants exchange gases
by diffusion, there are lots of gases moving to and from in plants, and this movement happens by diffusion