How does a nervous impulse begin

What is Na2SO4? an acid a base a salt an ion

Are humans considered consumers, decomposers, or producers?

Which of these groups is the smallest level of classification

Which is more likely to be dangerous-a volcano that erupts frequently or a volcano that has been inactive for a hundred years? Why?

If cells are grown in a medium containing radioactive 32P-labeled phosphate, which of these molecules will be labeled? A. amino acids B. nucleic acids C. glucose D. proteins

A scientific name has to refer to what

The changes in the surrounding environment can have an effect on plants too for a few weeks on the autumn season normally green leaves of deciduous plants acquire a red to yellow color how and why does this change in color happen?

Many of the biochemical reactions that occur within cells are catalyzed by enzymes. Which of the following statements is true about most enzyme-assisted reactions?

A cheeseburger from a fast food restaurant contains 19 g of fat, 20 g of carbohydrate, and 28 g of protein. How many kcal of energy does the cheeseburger contain

How do enzymes catalyze chemical reactions (don't just say "they lower the activation energy", give me specific mechanisms) ?