Biology B4 - Respiration

3 reasons we need energy

-for movement

-to keep warm

-for chemical reactions to build larger molecules e.g proteins are made by chemically joining amino acids

what type of reaction is energy

exothermic because it releases energy

when does respiration take place

continually in all living cells

what is the word formula for aerobic respiration

glucose + oxygen --> carbon dioxide + water. it releases energy

why does aerobic respiration release a lot of energy

because the glucose molecule has been fully oxidised

when is aerobic respiration carried out

when oxygen is present

if there is not enough oxygen what do cells carry out

anaerobic respiration

why do muscle cells need a lot of energy

for contraction

what happens when there is a shortage of oxygen

muscle cells respire anaerobically

What is the word equation for anaerobic respiration in muscles?

glucose ---> lactic acid

during anaerobic respiration in muscle cells what is glucose converted to

lactic acid

does anaerobic respiration require oxygen

no

why does anaerobic respiration release much less energy than aerobic respiration

because in anaerobic respiration, the oxidation of glucose is incomplete

Where else does anaerobic respiration take place

plant & yeast cells

what is the word equation for anaerobic respiration in plant/yeast cells

glucose ---> ethanol + carbon dioxide

what is anaerobic respiration in yeast cells called

fermentation

what do we use this reaction to make

alcoholic drinks such as beer

what is the alcohol in these drinks and how are they produced

ethanol produced by fergmentation

how is carbon dioxide in yeast produced by fergmentation useful in bread

creates air bubbles in the dough causing bread to rise