Bioenergetics Flashcards
photosynthesis equation
carbon dioxide + water -light->
glucose + oxygen
6CO2+6H2O–>C6H12O6+6O2
what type of reaction is photosynthesis?
endothermic as chloroplasts take in light
what factors affect the rate of photosynthesis?
- temp
- light intensity
- CO2 concentration
- amount of chlorophyll
shortage of any of these=photosynthesis can’t occur at maximum rate
how to control limiting factors in a greenhouse?
- greenhouse=traps heat=temp x limit photosynthesis
- x shades on ceiling=maximum light
- artificial light for winter/dark hours= photosynthesis all day round
- ventilation= plants x too hot
- heater burns paraffin=CO2 released=bad for planet
- hydroponics (watering system)= plants well watered
- easier to control pests & diseases+ fertilisers= maximise growth
light intensity equation
inverse square law (light+distance)
- 1/d^2
required practical: light intensity
- Pour 45 cm3 of sodium hydrogencarbonate solution in a boiling tube
- Cut a piece of the pondweed
- Place pondweed into boiling tube carefully to ensure no damage
- Put boiling tube 10 cm away from the light source. Allow the boiling tube to stand for five minutes
- Count the number of bubbles released in one minute. Record results. Repeat 3 times and record your results
- Calculate the average number of bubbles produced per minute
- Repeat the experiment at different distances away from the light source
- Plot results in a graph
what are the uses of glucose in a plant?
- respiration
- converted into insoluble starch for storage
- produce fat or oil for storage
- produce cellulose, which strengthens the cell wall
- combined with nitrate ions in the soil to form amino acids for protein synthesis.
what type of equation is respiration?
exothermic, it release energy for living processes
what are the 2 types of respiration?
aerobic and anaerobic
what do we need energy for?
- movement
- keeping warm
- chemical reactions to build larger molecules
aerobic respiration equation
glucose + oxygen –> carbon dioxide + water
C6H12O6+6O2–> 6CO2+6H2O
anaerobic respiration equation
glucose –>lactic acid
releases less energy
when does anaerobic respiration occur?
intense exercise
not enough oxygen available
what happens during exercise?
- heart rate+breathing rate+breath volume= increase= more oxygenated blood to muscles
- insufficient oxygen suppplied= anaerobic respiration= lactic acid builds up+oxygen debt
- long exercise period=muscles fatigued=muscles x contract efficiently
how do we get rid of lactic acid?
Blood transports lactic acid to
liver where it is converted back into glucose
