Respiration Flashcards
(22 cards)
what is respiration?
the breakdown of food to release energy
where does respiration occur?
in the cytoplasm and/or mitochondria of all living cells
what is the form of energy stored in food?
chemical energy
what foods contain the most energy per gram
fats
carbohydrates
proteins
how would you measure the energy content of food?
burn a piece of food beneath a test tube full of water
use the formula for the energy content of food to calculate the energy content
what is the word equation for the energy in food?
energy in food = mass of water x temperature rise x 4.2
what is the balanced formula equation for cell respiration?
C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP
glucose + oxygen -> carbon dioxide + water + energy
what is ATP?
a molecule produced during respiration that can be broken down to release energy
what is energy needed for?
- muscle contraction
- active transport
- building large molecules
- cell division
- maintaining body temperature
what is the formula for anaerobic respiration in plants and fungi (in words and symbols)
glucose -> ethanol + carbon dioxide + energy
C6H12O6 -> 2C2H5OH + 2CO2 + energy
what is the formula for anaerobic respiration in animals?
glucose -> lactic acid + energy
C6H12O6 -> 2C3H6O3 + energy
what is anaerobic respiration in fungi useful for?
beer, wine and bread making
what is repaying the oxygen debt?
the breaking down of lactic acid when oxygen becomes available following exercise
what are the key differences between anaerobic and aerobic respiration?
aerobic - uses oxygen
- produces a lot of ATP
- occurs in mitochondria
- CO2 and H2O is produces
anaerobic - does not use oxygen
- produces a small amount of ATP
- occurs in cytoplasm
- lactic acid or ethanol is produced
what is a practical to determine the heat produced by respiration?
two flasks of seeds must be set up containing thermometers
one set of seeds must be live and the other must be dead
the temperature change should be measured over a set period of time
what does hydrogencarbonate indicator do?
measures carbon dioxide levels
it is red in equilibrium
it is orange/yellow with increased CO2 levels
it is magenta as carbon dioxide is removed
describe an experiment to determine anaerobic respiration in yeast
glucose solution and yeast must be set up in a test tube beneath a layer of liquid paraffin in a water bath with a thermometer measuring the water temperature
a cork with a tube in it must seal the test tube, leading from the tube of yeast to a level of lime water
if the lime water turns cloudy as bubbles are produced from the yeast tube, CO2 is being produced
what will happen to the rate of respiration at very low and very high temperatures and why?
at very low respiration will slow down
at very high respiration will stop altogether
this is because respiration is controlled by enzymes
why is more oxygen carried to working muscles during exercise?
the muscles use more energy during exercise, so they need mor oxygen to continue to respire aerobically
if they cannot get enough oxygen they will begin to respire anaerobically and lactic acid will build up
where does aerobic respiration occur?
in the mitochondria of a cell
what is another name for anaerobic respiration in yeast cells
fermentation
what is the formula for fermentation?
glucose -> ethanol + CO2
