In this article we will discuss about the mechanism of eukaryotic gene expression, particularly in humans. 1. In multicellular organism, each cell expresses a subset of its genes. 2. A cell expresses different genes depending on its growth state or environment. 3. Sometimes gene transcripts are spliced differently in different cells. 4. Each gene carries not only structural information but [...]
In this article we will discuss about the physical basis of heredity with theories investigated by a great number of workers, some of whose results are as follows: Encasement Theory: One of the older, but now abandoned, ideas was set forth in the preformation or encasement theory, which supposed that the germs of all future generation were encased one within [...]
The morphologic characteristics of chromosomes are best studied during metaphase and anaphase of cell division. The chromosome was supposed to be covered by a membranous Pellicle. Electron microscope studies later showed that there is no definite membranous pellicle surrounding the chromosomes. A matrix of some sort, possibly protein, lipid, may be present. Other structures present in the chromosome include the [...]