carbohydrates

vitamins

proteins

nucleic acids.

transient and unstable

permanent and stable

transient but stable

permanent but unstable.

Lecithin - a phosphorylated glyceride found in cell membrane.

Palmitic acid - an unsaturated fatty acid with 18 carbon atoms.

Adenylic acid - adenosine with a glucose phosphate molecule.

Alanine amino acid - contains an amino group and an acidic group anywhere in the molecule.

Anabaena and Nostoc are capable of fixing nitrogen in free-living state also

Root module forming nitrogen fixers live as aerobes under free-living conditions.

Phosphorus is a constituent of cell membrances, certain nucleic acids and all proteins.

Nitrosomonas and Nitrobacter are chemo-autotrophs.