College-Biology True/False?

[angelicasongs]

I've been working on a bio. review sheet, and I always mess up on the true/false and fill-in-the-blank section. I just wanted to check my answers because I wasn't sure about some of them so here's the 10 T/F. Thanks!!!!

1.Enzymes work by lowering the free change of a reaction.
2.The Krebs cycle is a carbon reduction cycle.
3.Heat is commonly used to overcome the activation energy in biological reactions.
4.A kinase is an enzyme that often controls the activity of other enzymes.
5.In fermentation, pyruvate is oxidized.
6.Without oxygen photosynethesis would come to a halt.
7.The greater the activation energy, the slower a reaction will proceed.
8.Plant cells can contain both chloroplasts and mitochondria.
9.Fermentation produces less useable energy than aerobic respiration.
10.The sun provides the energy that is needed for photosynthesis.