2- respiration Flashcards
organisms need energy for things such as
chemical reactions, muscle contractions, keeping warm
cellular respiration is a
exothermic reaction that is continuously occurring in living cells
the chemical process of cellular respiration releases
energy from glucose. the energy is transferred via the molecule Adenosine Triphosphate (ATP)
ATP is produced in
respiration in the mitochondria, it is required for living processes to occur within cells and organisms
aerobic respiration
the chemical reaction in cells that uses oxygen to break down nutrient molecules to release energy
aerobic respiration is the
complete breakdown of glucose to release a relatively large amount of energy for use in cell processes and reactions. carbon dioxide and water are produced as waste products as well as releasing useful cellular energy
aerobic respiration word equation
glucose + oxygen -> carbon dioxide + water
chemical equation for aerobic respiration
C6H12O6 + 6O2 -> 6CO2 + 6H2O
anaerobic respiration
the chemical reaction in cells that breaks down nutrient molecules to release energy without using oxygen
anaerobic respiration involves
the incomplete breakdown of glucose and so releases a relatively small amount of energy for use in cell processes
anaerobic respiration in animals mainly takes place
in muscle cells during vigorous exercisze
anaerobic respiration in humans
glucose -> lactic acid
chemical equation for anaerobic respiration in humans
C6H12O6 -> 2C3H6O3
lactic acid builds up in
muscle cells and lowers pH of the muscle tissue which makes conditions more acidic. acidic conditions can denature the enzymes in cells
lactic acid will eventually be broken down by
using oxygen to produce carbon dioxide and water as waste products
the amount of oxygen required to break down the lactic acid is referred to as
the oxygen dept
the process of breaking down lactic acid is
known as the repaying the oxygen debt
plants and yeast can respire without
oxygen , breaking down the glucose in the absence of oxygen to produce ethanol and carbon dioxide
anaerobic respiration in yeast is called
fermentation
word equation for anaerobic respiration in plants and fungi
glucose -> alcohol + carbon dioxide
chemical equation for anaerobic respiration in plants and fungi
C6H12O6 -> 2C2H5OH + 2CO2
aerobic/anaerobic respiration- oxygen needed?
aerobic- yes
anaerobic- no
aerobic/anaerobic respiration- glucose breakdown
aerobic- complete
anaerobic- incomplete
aerobic/anaerobic respiration- products
aerobic- carbon dioxide and water
anaerobic- animal cell=lactic acid yeast =carbon dioxide and ethanol
aerobic/anaerobic respiration- energy released
aerobic- a lot
anaerobic- a little
apparatus needed to demonstrate the production of carbon dioxide
boiling tubes, rubber bands, hydrogen carbonate indicator solution, cotton wool, glass beads, germinating seeds, boiling/dead seeds
method to demonstrate the production of carbon dioxide
1) measure out 10cm3 of hydrogencarbonate indicator into 3 boiling tubes
2) put a layer of cotton wool
3) place 10 germinating seeds into tube A, 10 boiled/dead seeds into tube B, 10 glass beads into tube C
4) seal each tube with a rubber band
5) after 3 hours observe the colour of the indicator
hydrogen carbonate indicator results
orange in atmospheric CO2 levels, in high CO2 levels the indicator absorbs the CO2 and becomes yellow, in low CO2 levels it loses CO2 and becomes purple
results when demonstrating the production of carbon dioxide
tube A= yellow as seeds are respiring and producing carbon dioxide
tube B= remain orange as the dead seeds produce no carbon dioxide
tube C= remain orange as there is no living material
apparatus needed to demonstrate the production of heat
vacuum flasks, thermometer, cotton wool, germinating seeds, dead/boilded seeds
method to demonstrate the production of heat
1) set up flask A with germinating seeds and B with dead seeds
2) make sure cotton wool is plugged the top of each flask
3) hold the thermometer in place with the cotton wool
4) invert the flask
5) record initial temperature
6) after 4 days record the final temperature
results when demonstrating the production of heat
the thermometer in the flask with the germinating seeds (flask B) should show an in crease in temperature. flask A should remain room temperature. this is because the seeds in flask B are respiring and producing heat energy in the process. this shows that respiration is an exothermic reaction. the seeds in flask A are not respiring because they are dead, so the temperature remains the same
corms when demonstrating the production of carbon dioxide
c- we will change the content of the boiling tube (germinating seed, dead seed, glass beads)
o- the seeds used should all be of the same age, size and species
r- we will repeat the investigation several times to ensure our results are reliable
m- we will observe the change in the hydrogen carbonate indicator after 3 hours
s- we will control the volume of hydrogen carbonate indicator, the number of seeds/beads, the temperature of the environment
corms when demonstrating the production of heat
c- we will change the content of the flasks (germinating seeds or dead seeds)
o- the seeds used should all be of the same age, size and species
r- we will repeat the investigation several times to ensure our results are reliable
m- we will observe the change in the temperature on the thermometer
s- we will control the number of seeds, the starting temp, the material and size of the flasks
