aerobic respiration :
- occurs when there is enough supply of oxygen
- takes place in the mitochondria
- oxidation of glucose in the presence of oxygen to carbon dioxide, water and energy
- aerobic organisms respire aerobically
- C6H12O6 (gluclose) + 6O2 (oxygen) --> 6CO2 + 6H2O + 2898 kJ (energy)
- 38 molecules of ATP (2898 kJ/mol) is released
- energy is used to synthesise adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and inorganic phosphate
- ADP + phosphate + energy --> ATP
- ATP-- instant source of energy-- main energy supply for all living things
- the phosphate bonds of each ATP molecule can be easily broken down to release energy
anaerobic respiration :
- occurs when there is no more supply of oxygen
- breaks down glucose
- anaerobes respire anaerobically -- bacteria and certain types of yeast
- an active contracting muscle is capable of carrying out this process
- occurs in the cytoplasm
anaerobic respiration which occurs in human muscles :
- during vigorous exercise
- in spite of the increased breathing and heartbeat rate, the blood cannot supply oxygen fast enough
- the muscles are inthe state of oxygen dificiency, oxygen debt occurs
- glucose molecules breaks down partially into lactic acid
- releases 2 molecules of ATP (150 kJ/mol)
- much energy is trapped within the molecules of lactic acid
- C6H12O6 --> 2C3H6O3 (lactic acid) + 150 kJ
- accumulation of lactic acid can reach a high level of concentration which can cause muscle cramps and fatigue
- after a period of intense exercise, a person needs to breathe in deeply and rapidly in orsder to inhale more oxygen
- excess oxygen is used by the body to oxidise the accumulated lactic acid to carbon dioxide and water
- oxidation of lactic acid occurs mainly in the liver
- a portion of the lactic acid is oxidised to produce energy
- the remaining is converted into glycogen and stored in the muscle cells
- oxygen debt is paid off when all the lactic acid is removed
- oxygen debt-- amount of oxygen needed to remove lactic acid from the muscle cells
anaerobic respiration of yeast :
- produces ethanol, carbon dioxide and energy
- the process is known as fermentation and is catalysed by the enzyme zymase
- C6H12O6--> 2C2H5OH (ethanol) + 2CO2 + 210 kJ (energy)
- brewing industry and bread making (ethanol evaporates.. so thats why the bread we eat don't taste like alcohol! lol)
err.. don't think i'm that smart lo.. i didn't memorise everything up here.. HAHA...
hmm.. so add maths very teruk.. at first i get everything but then i got blurred in the end.. now still working on it! hmph! i cannot be confused... argh!
just now, was doing add maths.. and i couldn't think anymore.. had a slight headache so i went to sleep.. for 1 and a half hour.. then i just gotta get up.. haiz...
No comments:
Post a Comment