5 public questions tagged with this topic.
Predation is not mutualism because it benefits only one species while harming the other.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Interactions - Mutualism and Amensalism
Uric acid is the least toxic nitrogenous waste and is excreted in a water-insoluble form.
Ref: NCERT Class 11 Biology Chapter 16: Excretory Products and their Elimination Modes of Excretion - Ammonotelism Ureotelism Uricotelism
Glycolysis is an anaerobic process and does not directly require oxygen.
Ref: NCERT Class 11 Biology Chapter 12: Respiration in Plants Glycolysis - EMP Pathway and Link Reaction
Molecular cloning involves several enzymatic manipulations. Klenow fragment, lacking 5' exonuclease activity, can fill 5' overhangs to blunt ends using dNTPs. Isocaudomers XhoI and SalI generate compatible TCGA overhangs permitting cross-ligation. Alkaline phosphatase removes 5'-phosphate groups rather than 3'-phosphates, blocking self-ligation. Blue-white screening depends on alpha-complementation of lacZ; insertion inactivates beta-galactosidase producing white colonies on X-gal. However, white phenotype does not guarantee recombinant insert because vector mutations, primer dimers, or small non-disruptive inserts can also abolish activity, necessitating PCR or restriction verification rather than relying solely on color.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.
The enzyme undergoes a conformational change upon binding is the correct choice because it does not accurately describe or belong to the category addressed in this question. In the context of Enzymes Basics, the other options (The substrate fits perfectly into the enzyme’s active site, This model explains high specificity of enzymes, and It was proposed by Emil Fischer) are all valid and well-established concepts. The enzyme undergoes a conformational change upon binding is either unrelated to the topic, describes a different biological process, or represents a common misconception. Questions framed as 'which is NOT' require students to identify the exception among otherwise correct statements, demanding comprehensive knowledge of the topic rather than recognition of a single fact.
Ref: Lehninger Principles of Biochemistry, Nelson & Cox, 8th Ed., Ch. 6
