Question

How does temperature affect cellular respiration?

Answer 1

The rate of cellular respiration will increase with increased temperature, but there is an upper limit to this. It's important to know that cellular respiration depends on enzymes!

Explanation:

As temperatures go up, the motion of particles increases. Increased particle speed will mean more collisions between substrate (reactants) and enzymes. The more often enzymes interact with substrate molecules the faster the reaction will go.

Try running this simulation (try using 5 enzymes and 20 substrates) at different temperatures to see why this is true. The image below is a screenshot of the simulation.

Here is a video of an experiment testing the rate of respiration in yeast at different temperature levels.

If the temperature goes too high, the enzymes responsible for cellular respiration will denature. This will result in the reaction going slower (as more of the enzyme molecules denature). Eventually, high enough temperatures will denature all of the enzymes and the reactions will stop completely.

Here is footage of a test of catalase enzyme after it has been heated to the point of denaturing all of the enzyme.

Hope this helps!