The following points highlight the three main components of a Neuron. The components are: 1. Perikaryon 2. Axon 3. Myelin Sheath and Myelinogenesis. Neuron: Components # 1. Perikaryon: (a) Its diameter varies from 5µ to 125µ. (b) It has a cell membrane, cytoplasm, a large vesicular nucleus containing a single prominent nucleolus, numerous rod-like or spherical mitochondria, and a Golgi [...]
In this article we will discuss about the Intercellular Contact and Communication of Plasma Membranes. Cells have developed specialized regions on their membranes for intercellular communication. Gap junctions mediate and regulate the passage of ions and small molecules through a narrow hydrophilic pore connecting the cytoplasm's of adjacent cells. These pores are composed of subunits called "connexions". Connexions consist of [...]
The following points highlight the three major causes of cancer. The causes are: 1. Radiant Energy 2. Chemical Compounds 3. Oncogenic Viruses. Cause # 1. Radiant Energy: (a) Ultraviolet rays, X-rays, and y-rays damage DNA in several ways. (b) Ultraviolet radiation may cause pyrimidine dimers to form. (c) Apurinic or apyrimidinic sites may form by elimination of corresponding bases. Single [...]