NEET · Biology doubts
340 doubts found
Why are lichens used as indicators of air pollution?
A lichen is a symbiosis: a fungus provides shelter and water while an alga (or cyanobacterium) photosynthesises food.
Potato, ginger, onion and carrot are all 'underground vegetables' — are they the same kind of organ?
No — they're different modified organs.
Why is wood so strong and useful for building, even though it comes from a living tree?
Wood is mostly xylem.
Why do tiny water droplets appear on the tips of grass and leaves early in the morning?
At night transpiration nearly stops, but the roots keep actively absorbing water and minerals, building up root pressure.
How do growers make seedless grapes bigger, or a rooting powder help cuttings grow roots?
Two hormones are used.
Why do your muscles ache and tire during hard exercise, and sometimes cramp?
During intense effort the muscles need more oxygen than the blood can supply, so they switch to anaerobic respiration to keep making ATP.
Why do wind-pollinated plants (like grasses) release so much pollen, and why does it trigger allergies?
Wind is a random, wasteful carrier — most pollen never lands on the right stigma — so these plants compensate by producing enormous quantities of very light, dry pollen that drifts far on the breeze.
How is cattle dung turned into biogas for cooking, and why is it 'green' fuel?
In a biogas plant, cattle dung and water are digested by anaerobic bacteria, including methanogens (found in the gut of cattle).
What does “Law of dominance” actually mean in Principles of Inheritance and Variation, and why does it matter for NEET?
in a heterozygote only the dominant allele is expressed while the recessive one stays masked.
What does “DNA double helix” actually mean in Molecular Basis of Inheritance, and why does it matter for NEET?
two antiparallel strands held together by complementary base pairs, A with T and G with C.
I keep getting “Homologous vs analogous organs” questions wrong in Evolution. What's the trap?
treating any organs that do the same job as evidence of common ancestry.
I keep getting “Double circulation” questions wrong in Body Fluids and Circulation. What's the trap?
thinking human circulation is single like a fish's.
What does “Synapse” actually mean in Neural Control and Coordination, and why does it matter for NEET?
a junction where the impulse is carried across a gap by neurotransmitter molecules, in one direction only.
I keep getting “Ten per cent law” questions wrong in Ecosystem. What's the trap?
thinking most of the energy moves up to the next level.
I keep getting “Restriction enzymes” questions wrong in Biotechnology - Principles and Processes. What's the trap?
thinking they cut DNA at random positions.
I keep getting “Innate vs acquired immunity” questions wrong in Human Health and Disease. What's the trap?
thinking all immunity is present from birth.
What does “Mitochondria” actually mean in Cell: The Unit of Life, and why does it matter for NEET?
the powerhouse of the cell, where aerobic respiration makes most of the ATP; it has its own DNA.
What does “Proteins” actually mean in Biomolecules, and why does it matter for NEET?
polymers of amino acids that build tissues, act as enzymes, and transport molecules.
What does “Meiosis” actually mean in Cell Cycle & Cell Division, and why does it matter for NEET?
reductional division producing four genetically different haploid gametes.
What does “Chlorophyll” actually mean in Photosynthesis in Higher Plants, and why does it matter for NEET?
the green pigment that absorbs mainly red and blue light and reflects green.
What does “Fermentation” actually mean in Respiration in Plants, and why does it matter for NEET?
anaerobic breakdown of pyruvate into ethanol or lactic acid, releasing very little ATP.
What does “Bile” actually mean in Digestion & Absorption, and why does it matter for NEET?
a liver secretion (stored in the gall bladder) that emulsifies fats into small droplets.
What does “Carbon dioxide transport” actually mean in Breathing & Exchange of Gases, and why does it matter for NEET?
most CO₂ travels in the blood as bicarbonate ions.
What does “Blood components” actually mean in Body Fluids & Circulation, and why does it matter for NEET?
plasma (fluid), red cells (carry O₂), white cells (defence) and platelets (clotting).