Enzymes are biological molecules that act as catalysts in various biochemical reactions. They are essential for life as they speed up the rates of reactions by lowering the activation energy required for the reaction to occur. Enzymes are commonly referred to as biocatalysts and are primarily made up of proteins.

Proteins:
- Enzymes are primarily composed of proteins, which are macromolecules made up of amino acids.
- Proteins are formed by the linkage of amino acids through peptide bonds.
- Enzymes exhibit a high degree of specificity towards their substrates due to the unique arrangement of amino acids within their structure.
- The structure and properties of enzymes are determined by the sequence of amino acids.

Biocatalysts:
- Enzymes are known as biocatalysts because they accelerate the rate of chemical reactions in living organisms.
- They do so by providing an alternative reaction pathway with a lower activation energy.
- Enzymes remain unchanged after the reaction, allowing them to be used repeatedly.
- Enzymes are highly efficient catalysts, often increasing the reaction rate by millions or even billions of times.

Dinucleotides and Nucleic acids:
- Dinucleotides and nucleic acids are not correct terms to describe enzymes.
- Dinucleotides are molecules made up of two nucleotides, which are the building blocks of nucleic acids.
- Nucleic acids, such as DNA and RNA, are macromolecules that store and transmit genetic information.
- While some enzymes require cofactors, such as metal ions or coenzymes, which may include nucleotides, enzymes themselves are not classified as dinucleotides or nucleic acids.

In conclusion, the correct terms to describe enzymes are proteins and biocatalysts. Enzymes are protein molecules that act as highly efficient catalysts in biological reactions, speeding up the rates of reactions by lowering the activation energy.