The following points highlight the four major phases of the cell cycle. The phases are: 1. G1 (gap1) phase 2. S (synthesis) phase 3. G2 (gap 2) phase 4. M (mitosis) phase. Cell Cycle: Phase # 1. G1 Phase: The G1 phase is set in immediately after the cell division. It is characterised by a change in the chromosome from [...]
The following points highlight the five main classes of chemical compounds in chromatin. The classes are: 1. Nucleic acids 2. Basic proteins or histones (protamines in sperm nuclei of some fishes and birds) 3. Acidic proteins (Non-Histones) 4. Lipoproteins 5. Associated inorganic molecules. Chemical Compounds in Chromatin: Class # 1. Nucleic Acids: The nucleic acids are of two types: (i) [...]
In this article we will discuss about the Inheritance of Shell Coiling in Snail. One of the classical examples of intricate relationship between maternal genotype and egg cytoplasm "phenotype" was studied in snails by Sturtevant. He showed that there are two strains of water snails (limnaea peregra) that differ each other in the direction of coiling of shell. Looking into [...]