Online microbiology and biology related notes by SAGAR ARYAL
Regulation of protein synthesis in Prokaryotes Regulation of protein synthesis is necessary in all cells. Particularly, in the prokaryotic cells, regulation is achieved by means of genetic units called operons alongside a number of related mechanisms as described below: Regulation of Protein Synthesis on the Basis of Nutrient Supply Prokaryotes respond to changes in their … Read moreRegulation of protein synthesis in Prokaryotes
Eukaryotic DNA Isolation Protocol Deoxyribonucleic acid (DNA) extraction is the process by which DNA is separated from proteins, membranes, and other cellular material contained in the cell from which it is recovered. In eukaryotic cells, such as human and plant cells, DNA is organized as chromosomes in an organelle called the nucleus. These cells also … Read moreEukaryotic DNA Isolation Protocol
RNA Isolation Protocol Total RNA isolation from Bacterial Cells Principle of RNA Isolation Total RNA is isolated and separated from DNA and protein after extraction with a solution called as Trizol. Trizol is an acidic solution containing guanidinium thiocyanate (GITC), phenol and chloroform. GITC irreversibly denatures proteins and RNases. This is followed by centrifugation. Under … Read moreRNA Isolation Protocol
Extranuclear Inheritance- Cytoplasmic Factors and Types Though, the genes of nuclear chromosomes have a significant and key role in the inheritance of almost all traits from generations to generations, they altogether cannot be considered as the sole vehicles of inheritance. Certain experimental evidences suggest the occurrence of certain extranuclear genes or DNA molecules in the … Read moreExtranuclear Inheritance- Cytoplasmic Factors and Types
Hardy-Weinberg Equilibrium The Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem, or law explains that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. The law was proposed by a British mathematician Hardy and a German physician Weinberg (1908) independently. Both the ideas together is called … Read moreHardy-Weinberg Equilibrium
Chromosomes- Abnormalities and Disorders Chromosomes refer to any of the rod-shaped or threadlike DNA-containing structures of cellular organisms that are located in the nucleus of eukaryotes, are usually ring-shaped in prokaryotes (such as bacteria), and contain all or most of the genes of the organism. Simply put, it is a strand of DNA that is … Read moreChromosomes- Abnormalities and Disorders
Translation (Protein Synthesis) in Eukaryotes Translation involves translating the sequence of a messenger RNA (mRNA) molecule to a sequence of amino acids during protein synthesis. It is the process in which ribosomes in the cytoplasm or ER synthesize proteins after the process of transcription of DNA to RNA. The Ribosomes Ribosomes exist normally as separate subunits that are composed of protein and rRNA. Eukaryotic ribosomes are larger (80S) … Read moreTranslation (Protein Synthesis) in Eukaryotes
Sex-linked Inheritance Sex makes no difference in Mendel’s crosses. But the Mendel’s laws are not applicable on those genes which are exclusively located either in X or Y chromosome. Sex-Linked Inheritance is the inheritance of a trait (phenotype) that is determined by a gene located on one of the sex chromosomes. The genes which occur … Read moreSex-linked Inheritance
Linkage- Characteristics, Types and Significance Each chromosome contains more than one gene. The genes for different characters may be either situated in the same chromosome or in different chromosomes. When the genes are situated in different chromosomes, the characters they control appear in the next generation together or apart, depending on the chance alone. They … Read moreLinkage- Characteristics, Types and Significance
Eukaryotic Transcription Transcription is the process by which the information in a strand of DNA is copied into a new molecule of RNA. It is the first step of gene expression, in which a particular segment of DNA is copied into RNA (especially mRNA) by the enzyme RNA polymerase. It results into a complementary, antiparallel RNA strand called a primary transcript. Transcription in Eukaryotes Transcription occurs in eukaryotes … Read moreEukaryotic Transcription