The method used here is agarose gel elecrtrophoresis in which DNA ladder is used which is a set of standard used to determine the size of DNA used .The DNA ladder is put adjacent to the DNA fragments to be visualized Suppose if the ladder shows 300 basepair so the DNA adjacent to this number will be of this size.These are the set standards used to determine the size of DNA or RNA. For a range we can take 2% of agrarose to run DNA fragments upto 500 Basepair. Most of the amplified DNA falls into this category size.
During transcription, the enzyme RNA polymerase (green) uses DNA as a template to produce a pre-mRNA transcript (pink). The pre-mRNA is processed to form a mature mRNA molecule that can be translated to build the protein molecule (polypeptide) encoded by the original gene.
Answer: Microtubules are straight and hollow tubular structures with no limiting membrane arranged in different bundles which are made of globular protein called tubulin while microfilaments are long and fine thread like structures which are made up of non tubular contractile protein called actin and myosin.
Explanation: Microtubules may function alone or join with other proteins to form more complex structures like cilia, flagella or centrioles and perform various functions like
1) Act as conveyer belts which allow movement of granules, vesicles, protein molecules and other organelles like mitochondria to different part of the cell.
2) Form the spindle fibers which separate the chromosomes during mitosis and responsible for the movement of centrioles.
Microfilaments are present throughout the cytoplasm. They are responsible for:
1) Give structure strength and provide resistance to cell against the pulling forces
2) Responsible for cellular movements like contraction, gliding and cytokinesis (partition of cytoplasm during cell division)
Answer: A: It becomes inactive.
Explanation: Pepsin works best at a pH of 2. And as the stomach has a very acidic condition, pepsin works well. But in the small intestine, the pH is about 8, which is too high for pepsin to function. Therefore, pepsin gets denatured in the small intestine.
