BOTANY WITH THE BASICS OF HYDROBOTANY (AQUATIC PLANTS OF UKRAINE) - B.Ye. Yakubenko - 2011

IV. PLANT ANATOMY AND MORPHOLOGY

Organic Compounds of Primary Origin

Nucleic Acids

High-molecular-weight compounds composed of NUCLEOTIDES are called Nucleic Acids. These are Biopolymers that can be referred to as polynucleotides. Large amounts of nucleic acids are found in seed embryos, buds, and the ROOT and SHOOT apical Meristems.

Nucleotides are complex Organic compounds. They consist of a pentose sugar (ribose or deoxyribose), purine (adenine and guanine) and pyrimidine (cytosine, uracil, thymine) nitrogenous bases, and phosphoric acid. There are two main Types of Nucleic acids: ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Their biological role is that DNA is responsible for storing and replicating hereditary information, while RNA is responsible for transmitting it during METABOLISM/35.html">Protein Biosynthesis.

As components of Viruses, nucleic acids play a crucial role in the reproduction of these life forms.

Purine and pyrimidine bases act as growth stimulants for plants and microorganisms. Purine bases (adenine, guanine) and their degradation products (hypoxanthine, xanthine, uric acid, allantoin) are widely distributed in nature. In addition to nucleic acids, they are components of numerous vital compounds, Enzymes, and adenosine triphosphate (ATP).

A number of plants contain free purine bases and their degradation products. Adenine and guanine have been detected in the leaves of tea, clover, field beans, and in Yeast. Hypoxanthine has been found in mustard and lupine seeds. Uric acid is present in field bean seeds. Allantoin occurs in tobacco and datura seeds, sugar beet roots, comfrey rhizomes, and other plants. Free uracil, thymine, and cytosine have been identified in field beans. The alkaloid caffeine (theine), obtained from tea leaves and coffee tree seeds, is a purine derivative. An adenine derivative, zeatin, serves as a Cell Division stimulant.