The following points highlight the five processes involved in transport of molecules across cell membrane. The processes are: 1. Passive Diffusion 2. Facilitated Diffusion 3. Active Transport 4. Group Translocation 5. Ion Transport through Ionophores. Process # 1. Passive Diffusion: By passive diffusion, molecules move across the membrane without interacting with any specific carrier protein in the cell membrane. The [...]
In this article we will discuss about the biosynthesis of various types of nucleotides:- 1. Pyrimidine Nucleotides 2. Purine Nucleotides. 1. Pyrimidine Nucleotides: Biosynthesis of pyrimidine nucleotides begins with condensation of a carbamyl residue of carbamyl phosphate with aspartic acid to produce carbamyl aspartate and inorganic phosphate. Carbamyl aspartate is dehydrated and cyclized to dihydro-orotic acid which is next dehydrogenated [...]
In this article we will discuss about the molecular structure of lipids. Lipids are another group of important biological molecules present in all cellular organisms and some viruses. Unlike the other groups of biological molecules, lipids are highly heterogenous in chemical structure. But all of them possess a common physical property which is that they are all non-polar compounds, insoluble [...]