In this article we will discuss about the Structure and Function of Microtubules and Cytoskeleton in Cell. Structure of Microtubules and Cytoskeleton in Cell: Microtubules are long, hollow tubular cylinders with an outer diameter of 250Å. The wall thickness is about 50Å, leaving a hollow core of about 150Å diameter. The length of microtubules varies from a fraction of a [...]
The below mentioned article provides a study note on Ribozyme and RNA World Hypothesis. According to this hypothesis primordial cells lacking protein synthesis use RNA both as the repository of genetic information and as enzymes that catalyse metabolism. Enzymatic catalysis which was earlier thought to be the exclusive domain of proteins, but is now established that RNA molecules can cut, [...]
The following points highlight the three main constituents of nucleus. The constituents are: 1. Nuclear Envelope 2. Nucleolus 3. Nucleoplasm. Constituent # 1. Nuclear Envelope: Under the electron microscope the nuclear envelope appears to consist of two membranes, the outer and the inner nuclear membranes, separated by a perinuclear space of 20 nm (Fig. 2.65). Each of the two membranes [...]