Nucleotides are the building block (monomer) units of the nucleic acids. They constitute about 2% of the protoplasm. A nucleotide is a condensation product of three chemicals - a pentose sugar, a nitrogenous base and one or more phosphate groups. (a) Pentose Sugars: Two types of pentose sugars occur in nucleotides - ribose (C5H10O5) and deoxyribose (C5H10O4). Both the sugars [...]
1. Water is highly cohesive and adhesive: Because of hydrogen bonds, water molecules develop strong intermolecular attraction between them. This is called cohesion. When water form hydrogen bonds with other substance, the attraction is called adhesion. Due to cohesion and adhesion, seeds swell and germinate; ascent of sap and capillary movement of water takes place. 2. Water has high tension: [...]
Read this article to learn about the Cycas: Occurrence, Morphological Features and Economic Importance ! Division : Cycadophyta Order : Cycadales Genus : Cycas Class : Cycadopsida Family : Cycadaceae Occurrence: Sixteen species of Cycas are found in the tropical and subtropical parts of the earth. The name Cycas has been derived from a Greek word Kykas = Cocopalm. It [...]