Welcome to Biology Notes Online! We are the BNO Team, dedicated to providing high-quality, accessible biology study notes for students and teachers alike. Our goal is to simplify complex biological concepts and present them in an easy-to-understand format, entirely free of charge. Whether you're preparing for exams, teaching a class, or simply passionate about biology, our comprehensive notes are designed to support your learning and teaching journey.
What is Photosystem 1 (PS1)? What is Photosystem 2 (PS2)? Difference between Photosystem 1 (PS1) and Photosystem 2 (PS2) Feature Photosystem I (PSI) Photosystem II (PSII) Location in Thylakoid Membrane Outer surface Inner surface Photocenter P700 P680 Absorbing Wavelength >680 nm <680 nm Photophosphorylation Both cyclic and non-cyclic Only non-cyclic Photolysis of Water No Yes … Read more
What is the Ninhydrin Test? The ninhydrin chemical test is used for determining whether an analyte contains any amines or amino acids. In this test, ninhydrin (a chemical compound with the formula C9H6O4; IUPAC name: 2,2-dihydroxyindane-1,3-dione) is added to a test solution of the analyte. The formation of a deep blue color within the test … Read more
Objective of Phenylalanine Deaminase Test Principle of Phenylalanine Deaminase Test Requirements For the test Composition of Phenylalanine agar DL-Phenylalanine: 2 gm Yeast extract: 3 gm Sodium chloride: 5 gm Disodium phosphate: 1 gm Agar: 12 gm Distilled water: 1000 ml pH: 7.3 Preparation of Phenylalanine agar slant Note: Following autoclaving, the medium should appear lighter … Read more
Unsaturated fish oils are especially vulnerable to oxidation, resulting in peroxides when stored in cold or freezing conditions for storage. Peroxides are precursors to breakdown products that can cause rancid taste in fat. Peroxide levels are an indicator of oxidation in the initial stages of lipid degradation. The index is less reliable in the latter … Read more
Picric acid test is used for reducing sugars, and is a highly sensitive chemical tests. Picric acid reactions (toxic yellow crystal solid) which is also referred to chemically as 2,4 6-trinitrophenol (TNP) reacts with sugars that are reduced to create Picramic Acid that is red-colored. The Picric Acid test is made up of a sugar … Read more
Nelson-Somogyi method can be used to quantify the reduction of sugar using arsenolmolibdat and copper reagents. The principle behind the Nelson Somogyi method is the quantity of deposro oxide deposits which react with arsenomolibdate, which reduces to molybdine blue. The blue hue is determined by as absorbance. The keto and aldehyde free groups are regularly … Read more
The rapid furfural test is a type of chemical test which is used to determine the difference between fructose and glucose. The test for rapid furfural is like Molisch’s test however it utilizes concentrated hydrochloric acid instead of concentrated sulfuric acid, and the solution is then boiled. A dilute solution of sugar is added in … Read more
This is a test that is common for all carbohydrate larger than the tetroses. The test works on the basis that pentoses as well as hexoses can be dehydrated using conc. sulfuric acid, resulting in furfural or hydroxyl-methyl furfural or hydroxyl methyl furfural. These compounds condense with a-naphthol to create a purple condensation product. Molisch’s … Read more
Mucic acid test tests for lactose and galactose. The sugar is transformed into carboxylic acid using hot nitric acid. In order to produce dicarboxylic acids, aldoses are oxidized on each end of the open ring form. Chain fragmentation triggers ketoses to oxidize and produce a range of dicarboxylic acid. Galactraric acid (mucic acid) created by … Read more
What is Bial’s test? Bial’s Test is a type of chemical test which is used to determine the existence of pentoses. It was named in honor of Manfred Bial, a German doctor. The ingredients are orcinol, hydrochloric acid and ferric chloride. If Pentose is present it will dehydrated to form furfural that is then reacted … Read more
⚠️
Click on your ad blocker icon in your browser's toolbar
Select "Pause" or "Disable" for this website
Refresh the page if it doesn't automatically reload
7 min read 
