pre-class

Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous. The megaspores and microspores germinate and give rise to female and male gametophytes, respectively. The female gametophytes in these plants are retained on the parent sporophytes for variable periods. The development of the zygotes into young embryos take place within the female gametophytes. This event is a precursor to the seed habit considered an important step in evolution. Assertion – In gymnosperms, the male and female gametophytes depend on the sporophyte.

Assertion & Reason: Gametophyte Dependence in Gymnosperms Assertion (A): In gymnosperms, the male and female…

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NCERT-Continued self pollination lead to inbreeding depression

Inbreeding Depression in Plants Inbreeding Depression in Plants Inbreeding depression refers to the reduced biological…

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Plant Growth and Development-1-NCERT

Stage/Process Details 1. Development – Development is the sum of two processes: Growth and Differentiation.…

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FACTORS AFFECTING PHOTOSYNTHESIS – NCERT- NEET

Factor Description Light Quality Photosynthesis primarily uses red (650-700 nm) and blue (400-500 nm) light…

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Electrons generally move from a more negative (lower) or less positive redox potential to less negative or a more positive (higher) redox potential, reflecting a downhill energy flow. However, in the Z-scheme of photosynthesis, there are two key points where light energy is used to excite electrons, allowing them to move uphill to a more positive redox potential.

Electron Carrier Redox Potential (mV) Water (H₂O) +820 mV P680 (PSII reaction center) +1,200 mV…

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Biodiversity-2-NCERT-Species Diversity-According to the IUCN (2004), the total number of plant and animal species described so far is slightly more than 1.5 million

Category Type Number of Species Animals Total 10,50,000 Vertebrates 52,500 Fishes 25,000 Amphibians 5,750 Reptiles…

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Biodiversity-1 for NEET

Category Details Introduction An alien would be amazed by the enormous diversity of life on…

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ECOLOGICAL SUCCESSION for NEET – Conceptual Only

Concept Description Community Response to Environment Communities change in composition and structure over time in…

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The pyramid of biomass in sea is generally inverted because the biomass of fishes far exceeds that of phytoplankton. Isn’t that a paradox? How would you explain this

Concept/Reason Explanation Standing Crop The standing crop refers to the total biomass of organisms (like…

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NCERT-why in an aquatic ecosystem, Grazing Food Chain is the major conduit for energy flow. As against this, in a terrestrial ecosystem, a much larger fraction of energy flows through the detritus food chain than through the Grazing Food Chain .

Aspect Aquatic Ecosystem (Grazing Food Chain Dominant) Terrestrial Ecosystem (Detritus Food Chain Dominant) Primary Producers…

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