Chargaff’s rule is a key principle in molecular biology, stating that in DNA, the proportion of adenine (A) always equals that of thymine (T), and guanine (G) always equals cytosine (C). This A=T and G=C ratio varies between species but remains constant within an organism. This discovery helped Watson and […]
DNA ligase is an essential enzyme that facilitates the joining of DNA strands by catalyzing the formation of phosphodiester bonds between adjacent nucleotides. It plays a critical role in DNA replication and repair by sealing breaks or “nicks” in the sugar-phosphate backbone, particularly on the lagging strand where Okazaki fragments […]
DNA polymerase is an enzyme responsible for synthesizing new DNA strands during replication by adding nucleotides to a pre-existing strand using the original DNA as a template. It works in the 5′ to 3′ direction, ensuring accurate base-pairing to maintain genetic fidelity. DNA polymerase also has proofreading capabilities, correcting errors […]
RNA polymerase is an enzyme that synthesizes RNA from a DNA template during transcription. It binds to specific regions of the DNA called promoters and unwinds the DNA strands to read the sequence. RNA polymerase then assembles complementary RNA nucleotides to form a single-stranded RNA molecule. This RNA serves as […]
Archaebacteria, or archaea, are a group of single-celled microorganisms distinct from bacteria and eukaryotes. They thrive in extreme environments like hot springs, salt lakes, and deep-sea vents. Unlike bacteria, archaea have unique cell membranes and genetic material. They lack peptidoglycan in their cell walls, which sets them apart from true […]
Bacterial conjugation is a process where one bacterium transfers genetic material to another through direct contact. A donor cell with a plasmid forms a pilus to connect with a recipient cell, transferring genetic material that can lead to new traits or antibiotic resistance in the recipient. This is an MCQ […]
A restriction enzyme, or restriction endonuclease, is a protein produced by bacteria that cuts DNA at specific sequences, known as recognition sites. These enzymes serve as a defense mechanism against invading viruses by chopping up foreign DNA. In biotechnology, restriction enzymes are used for genetic engineering, as they allow precise […]
Restriction endonucleases, or restriction enzymes, are proteins that cut DNA at specific recognition sequences, usually palindromic. Found naturally in bacteria, they serve as a defense mechanism by cleaving foreign DNA, such as that of viruses. Each enzyme recognizes a particular sequence of nucleotides and cuts at or near this site, […]
Chromatography is a laboratory technique used to separate, identify, and analyze components in a mixture. It involves a stationary phase and a mobile phase. As the mixture moves through the stationary phase, different components travel at different rates, leading to separation. Types include gas, liquid, paper, and thin-layer chromatography, each […]