The Student Room Group
Reply 1
KP Nuts
I know what a limiting factor is but i'm having difficulty putting into words...what is the textbook definition for a limiting factor (i.e. would get full marks in an edexcel exam)?

I'm not doing edexcel, but surely it is a factor which could limit the rate of a reaction?
Reply 2
safe kris this is my def from my awesome mind lol any factor (biotic or abiotic) that either limits or completely inhibits the rate of a particular reaction. :cool:
Reply 3
Is that all you gotta put? Sweet, just rewrite the question
Reply 4
prolly you could state it this way tht it is a factor among the factors which is at its minimum value affecting the rate or productivity (well dont go on this one too much! i put it into my own words!)
Reply 5
Ok, am doing edxecel...

A limiting factor is something that is in low levels limits the rate of photosynthesis

When a limiting factor increases it would cause the rate of photosynthesis to increase

Until something else becomes a limiting factor,

examples of limiting factors... temperature (effects rate of enzyme activity - RuBiSCO), carbon dioxide concentration (used in the light independent reaction) or light intensity (needed for the loss of electrons from chlorophyll in the light dependent reaction)
A limiting factor is something that is limiting something from progressing further. It's the one factor that is dictating the rate at which something is happening. (the weakest link) so to speak.

Think of it this way.

If you are a running 100m sprint. Eating more chocolate and other things high in energy wont allow you to fun faster. The limiting factor will be how quickly anaerobic respiration can occur in your muscles. The limiting factor is your rate of respiration.

Now imagine you havn't eaten for two days and ran a marathon the day before. The limiting factor will be the amount of energy you have in your body and not your rate of respiration as your energy levels will be very low.
Reply 7
The limiting factor is NOT the rate of respiration...

It is what causes the rate of respiration to be limited!
Reply 8
I'd say,

a limiting factor is a factor that stops or lowers the rate of a reaction, despite the increase in a second factor which would otherwise increase the rate
Reply 9
joshdajoker
A limiting factor is something that is limiting something from progressing further. It's the one factor that is dictating the rate at which something is happening. (the weakest link) so to speak.

Think of it this way.

If you are a running 100m sprint. Eating more chocolate and other things high in energy wont allow you to fun faster. The limiting factor will be how quickly anaerobic respiration can occur in your muscles. The limiting factor is your rate of respiration.

Now imagine you havn't eaten for two days and ran a marathon the day before. The limiting factor will be the amount of energy you have in your body and not your rate of respiration as your energy levels will be very low.

That's a good way to think about it, I like that :smile: