NEET · Biology doubts
340 doubts found
What is the difference between PCR and gel electrophoresis?
PCR amplifies a DNA segment into many copies; gel electrophoresis separates DNA fragments by size using an electric field.
What is the difference between food chain and food web?
A food chain is a single linear feeding sequence; a food web is many interconnected chains showing all feeding relationships.
What does “Viruses” actually mean in Biological Classification, and why does it matter for NEET?
acellular particles of a nucleic acid core in a protein coat that can only reproduce inside a host cell.
What is the difference between tap root and fibrous root?
A tap root has one main root with smaller branches (dicots, e.g. mustard); a fibrous root system is a cluster of thin roots of similar size (monocots, e.g. grass).
What is the difference between monocot stem and dicot stem?
A monocot stem has scattered vascular bundles and no cambium (no secondary growth); a dicot stem has bundles in a ring with cambium, allowing it to thicken over years.
What is the difference between transpiration pull and root pressure?
Transpiration pull is the dominant leaf-driven suction that lifts water to great heights; root pressure is a weaker push from the roots, noticeable mainly at night (causing guttation).
What is the difference between auxin and ethylene?
Auxin promotes cell elongation, rooting and apical dominance; ethylene is a gas that ripens fruit and triggers ageing and leaf/fruit fall (abscission).
What is the difference between actin and myosin?
Actin is the thin filament; myosin is the thick filament whose heads pull on actin. Their sliding overlap shortens the muscle during contraction.
What is the difference between self-pollination and cross-pollination?
Self-pollination keeps traits pure but gives no variation; cross-pollination mixes genes from two plants, creating variation that helps a species adapt.
I keep getting “Biofertilisers” questions wrong in Microbes in Human Welfare. What's the trap?
assuming only chemical fertilisers can supply nitrogen.
I keep getting “Independent assortment” questions wrong in Principles of Inheritance and Variation. What's the trap?
applying independent assortment to genes that are linked on the same chromosome.
I keep getting “Genetic code” questions wrong in Molecular Basis of Inheritance. What's the trap?
thinking one codon can code for several amino acids.
What is the difference between divergent evolution and convergent evolution?
Divergent evolution makes related species differ as they adapt to new niches (homologous organs, Darwin's finches); convergent evolution makes unrelated species resemble one another for the same function (analogous organs, insect and bird wings).
What is the difference between artery and vein?
Arteries carry blood away from the heart (usually oxygenated, thick-walled, no valves); veins return blood to the heart (usually deoxygenated, thinner-walled, with valves). The pulmonary vessels are the exception.
How is Neural Control and Coordination tested in NEET, and what should I focus on?
Prioritise the core ideas: Nerve impulse, Synapse, Reflex arc.
What is the difference between food chain and food web?
A food chain is a single linear who-eats-whom path; a food web is many interlinked chains, which gives an ecosystem stability because alternative food routes exist.
What is the difference between cloning vector and host cell?
The vector (a plasmid or virus) carries the foreign gene; the host cell (like E. coli) takes up the vector and multiplies, producing many copies of the gene.
What is the difference between active immunity and passive immunity?
Active immunity is produced by one's own body after infection or vaccination and is long-lasting; passive immunity is borrowed ready-made antibodies (colostrum, antiserum) that act at once but fade quickly.
I keep getting “Cell membrane” questions wrong in Cell: The Unit of Life. What's the trap?
thinking the membrane lets everything pass freely.
I keep getting “Nucleic acids” questions wrong in Biomolecules. What's the trap?
thinking RNA cannot store genetic information (some viruses use RNA).
What is the difference between haploid and diploid?
Haploid (n) cells have one set of chromosomes (gametes); diploid (2n) cells have two sets (body cells).
How is Photosynthesis in Higher Plants tested in NEET, and what should I focus on?
Prioritise the core ideas: Light reactions, Calvin cycle (dark reaction), Chlorophyll.
What is the difference between glycolysis and Krebs cycle?
Glycolysis splits glucose to pyruvate in the cytoplasm (no O₂ needed); the Krebs cycle oxidises it fully in the mitochondria (aerobic).
What is the difference between pepsin and trypsin?
Pepsin digests protein in the acidic stomach; trypsin digests protein in the alkaline small intestine.