31 public questions tagged with this topic.
**Heat engine** absorbs Q_h from hot reservoir T_h, does work W, rejects Q_c to cold T_c, efficiency η = W/Q_h =1 - Q_c/Q_h, second law limits η
Ref: NCERT > Physics Book > Thermodynamics > Second Law Heat Engines and Kelvin-Planck
Atmospheric pressure decreases with altitude as the weight of the air column above reduces, a fundamental concept in the chapter’s discussion of pressure variation. As per NCERT, applying relevant law/formula with correct units and sign convention leads to It decreases with altitude. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.
Ref: NCBI Bookshelf, Ideal Gas Law: P1V1/T1 = P2V2/T2.
Bacteria play a key role in the nitrogen cycle by converting atmospheric nitrogen into forms usable by plants.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Organism and Environment - Major Biomes Abiotic Factors
Tissue culture is a technique that produces genetically identical plants through micropropagation from a_x000D_ single plant cell or tissue.
Ref: NCERT Class 12 Biology Chapter 10: Biotechnology and its Applications Medical Applications - Genetically Engineered Insulin
RNA interference (RNAi) silences specific gene expression using double-stranded RNA molecules.
Ref: NCERT Class 12 Biology Chapter 10: Biotechnology and its Applications Agricultural Applications - RNAi - Nematode Resistance
Homo habilis, also known as the 'handy man,' was the first hominid to use stone tools.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Darwin's finches are a classic example of adaptive radiation, where species evolved from a common ancestor to occupy different ecological niches.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Origin and Evolution of Man
Homo erectus used tools and fire, marking an important stage in human evolutionary development.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Origin and Evolution of Man
Embryological evidence, such as similar embryonic stages, supports the concept of common ancestry among species.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Evidences of Evolution - Paleontological and Comparative Anatomy
Hardy-Weinberg equilibrium remains stable only when no evolutionary forces are acting on a population.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Evidences of Evolution - Paleontological and Comparative Anatomy
Chemical evolution suggests that life originated from simple inorganic substances through gradual chemical processes.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Origin of Life - Theories Miller Urey Experiment
Louis Pasteur's experiment showed that life arises from pre-existing life, disproving the theory of spontaneous generation.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Origin of Life - Theories Miller Urey Experiment
