The acid-soluble pool represents roughly the cytoplasmic composition whereas the macromolecules from cytoplasm and organelles become the acid-insoluble fraction. Together they represent the entire chemical composition of living tissues or organisms. Al! the compounds which are found in the add-soluble pool, have their molecular weights ranging from approx. 18 to around 800 daltons (Da). The acid-insoluble fraction, has only four types of organic compounds i.e., proteins, nucleic acids, polysaccharides and lipid.So, the correct answer is 'Flavinoids and alkaloids'.