"both have no direct relationship but a free efficient expression binds them" what are they?

Answer

DNA and RNA

Explanation:

As the question indicates that they do not have a direct relationship with each other but there is an indirect process that links them. If we talk about molecular biology, DNA and RNA are two important molecules which form the basis of our every structure or function.  It is important for the timely activity of these two molecules so that every organism performs their activities timely.

Free efficient expression

if we say there is a free expression system that binds them it refers to the process of transcription and translation during which DNA is converted to RNA and RNA sequence is converted into a sequence of proteins. The synthesis of protein is the final stage where you can say that DNA and RNA are processed to form a final product that is protein.

Hope it help!

the answer is d. chordata

1. amino acid refers to the fundamental building block of proteins, comprising of an amino group and a carboxyl group.

2. catalyst refers to any substance, which increases the rate of chemical reaction without being used up in the reaction.

3. a complex molecule containing he genetic code is dna or deoxyribonucleic acid.

4. an enzyme refers to a molecule of protein, which is unique in accelerating up a particular chemical reaction in the biological systems.

5. nucleic acid refers to an sequence of sugars, phosphates, and nitrogenous bases, for example, dna and rna.

6. a protein refers to a large, composite organic molecule comprising of a huge number of amino acids associated together with the of peptide bonds.

7. rna refers to a nucleic acid that takes part in the production of proteins.

8. substrate refers to a compound, which takes part in a chemical reaction, and is chemically modified by the reaction.