Herbicides are chemicals that kill plants by interrupting important biological processes. Different herbicides affect different plant processes. The herbicide atrazine prevents the chemical reactions that use energy from sunlight. A plant is sprayed with atrazine.
Exposure to atrazine causes an immediate decrease in the production of two substances in plant. Select the substance.
A. DNA
B. Carbon dioxide
C. Oxygen
D. Phospholipids

oxygen because that's one of the substance that plants produce.

You can also do this by the process of elimination. Knowing that atrazine impedes the production of substances in plants, we know that it can't be DNA and Phospholipid. Carbon Dioxide is used by plant, not produced; thus, oxygen is the answer.

this protocol provides a detailed procedure for total protein extraction for western blot analysis from achieved samples following trizol isolation of rna.

but there is no

i guess you forgot putting it.