Where are Polyribosomes found?

Polyribosomes or polysome as name suggests, where two or more ribosomes translate mRNA into polypeptides. It helps to increase protein synthesis rate. Polyribosomes are found prokaryotes and eukaryotes both either free in the cytoplasm or can attach to the endoplasmic reticulum (ER) and the nucleus membranes. They are attached to rough endoplasmic reticulum surface and […]

Pharmacy abbreviation

Various abbreviations and symbols used in prescribing drugs 1. Before meals : ac It is an abbreviation on a prescription for before meals; Latin called “ante cibum”. 2. Twice a day : bid In prescription, b.i.d. means twice (means two times) a day. 3. Centimeter : cm 4. Discontinue : D/C 5. Dextrose 5% in […]

What is t4 DNA ligase?

T4 DNA ligase as the name suggests, ligase enzyme facilitates the joining of DNA strands together by forming phosphodiester bond. T4 is a phage. Therefore, T4 DNA ligase is a phage-encoded T4 DNA ligase that catalyzes a joining of DNA molecules. It is an ATP-dependent ligase which is produced during infection of E. coli by […]

You have isolated an E. coli mutant which grows very slowly. Upon further investigation, you discover that while DNA replication is successful in this mutant, it occurs much slower than in the wild type E.coli. Which enzyme would you suspect is mutated?

Answer: Out of Helicase, Sliding clamp, Primase, Ligase, Polymerase. I suspect sliding clamp to be mutated. Explanation: If helicase is mutated then DNA template strands cannot be separated. Therefore, new DNA will not synthesized. If primase is mutated then RNA primers will not able to begin DNA replication. If ligase is mutated then newly formed […]

Chargaff’s rule

According to Chargaff’s rule 1) Adenine (A) + Guanine (G) + Cytosine (C) + Thymine (T) =100% 2) Adenine is paired with Thymine by two hydrogen bonds and Cytosine paired with Guanine by three hydrogen bonds. Thus, amount concentration of guanine is equal to cytosine and adenine is equal to thymine. Guanine = Cytosine; Adenine […]

Functions Of Endoplasmic Reticulum

Endoplasmic reticulum is a continuous membrane system that is found throughout the cell with either ribosomes present or absent. If ribosomes present then it has rough surface. Thus, it is called as rough endoplasmic reticulum. If ribosomes are absent then it has smooth surface. Thus, called as smooth endoplasmic reticulum. Functions of Endoplasmic Reticulum: 1. […]

Importance of Ecosystem

Ecosystem is the interaction of living such as plants, animals, and bacteria and nonliving components such as air, water, soil, weather. Ecosystem size can be from a small tide pool to a giant desert and the members of that system are so interdependent or interconnected that any change of one factor can effect the entire […]

Greenhouse Effect

Greenhouse effect is natural process that allow life to exist on earth by maintaining the earth’s temperature at around 33 degrees Celsius. Earth gets sun’s light where visible light is absorbed that warms Earth and releases infrared radiation. It means surface is more hot, more the infrared radiation released. Some infrared radiation is absorbed by […]