Acidic dyes are anionic which means are negatively charged and thus react with positively charged and repulsed by negatively charged materials. They are called as negative stain and are attached to the background and stains it and cells are colorless. Basic dyes are cationic which means are positively charged. Therefore, it reacts with negatively charged […]
Cell Organelles and their Functions 1. Nucleus: Management Nucleus is the “Brain” that controls and manage all the functions of the cell. It protects or stores the genetic information such as DNA that contains instructions for the production of proteins. It is surrounded by the nuclear envelope. It is the control center of the cell. […]
Enzymes are macromolecular biological catalysts. The molecules upon which enzymes may act are called substrates and therefore the enzyme converts the substrates into different molecules referred to as products. Almost all metabolic processes within the cell need enzyme catalysis so as to occur at rates fast enough to sustain life. Metabolic pathways depend on substrate […]
When E. coli cells put in 20% NaCl solution then it gives hypertonic environment which means concentration of solutes are more on outside of a cell as compared to inside of a cell. Therefore, E. coli cells lose water to the environment because of movement of water out of the cell to an area of […]
Somatic vs Germline mutations All of the following types of mutations can be passed to offspring EXCEPT ______ mutations. -germ -frameshift -somatic -silent -nonsense 1) Answer: Somatic Explanation: Germ mutations occur in germ cells such as in egg and sperm cells. As germ mutations occur in reproductive cells and thus passed to next generation. Silent […]
Inducible vs. repressible operon Inducible and repressible operon is defined as operon response in the presence of metabolite. Genes are turned on in the presence of metabolite (e.g. lac) is called inducible operon. Genes are turned off in the presence of metabolite (e.g. trp) is called repressible operon. Example: Lac operon is inducible operon which […]
