NEET · Biology doubts
340 doubts found
What does “Aerobic respiration” actually mean in Respiration in Plants, and why does it matter for NEET?
the oxygen-using stages (Krebs cycle and electron transport chain) in mitochondria that yield most ATP.
What does “Absorption” actually mean in Digestion & Absorption, and why does it matter for NEET?
digested nutrients are absorbed mainly in the small intestine, whose villi hugely increase surface area.
What does “Oxygen transport” actually mean in Breathing & Exchange of Gases, and why does it matter for NEET?
most oxygen is carried by haemoglobin in red blood cells as oxyhaemoglobin.
What does “Heart chambers” actually mean in Body Fluids & Circulation, and why does it matter for NEET?
four chambers — two atria and two ventricles — keep oxygenated (left) and deoxygenated (right) blood separate.
What does “Urine formation” actually mean in Excretory Products & Elimination, and why does it matter for NEET?
ultrafiltration in the glomerulus, then selective reabsorption and secretion in the tubules.
What does “Nerve impulse” actually mean in Neural Control & Coordination, and why does it matter for NEET?
an electrical signal (action potential) travels within a neuron; a chemical signal crosses the synapse.
What does “Insulin and glucagon” actually mean in Chemical Coordination (Endocrine System), and why does it matter for NEET?
pancreatic hormones — insulin lowers blood glucose, glucagon raises it.
What does “Monohybrid ratio” actually mean in Principles of Inheritance & Variation, and why does it matter for NEET?
a cross of one trait gives a 3:1 phenotype ratio in the F2 generation.
What does “Semi-conservative replication” actually mean in Molecular Basis of Inheritance, and why does it matter for NEET?
each new DNA molecule keeps one original strand and one newly made strand.
What does “Variation and adaptation” actually mean in Evolution, and why does it matter for NEET?
inherited differences among individuals provide the raw material selection acts on.
What does “Active vs passive immunity” actually mean in Human Health & Disease, and why does it matter for NEET?
active immunity is when the body makes its own antibodies; passive immunity is receiving ready-made ones.
What does “Menstrual cycle” actually mean in Human Reproduction & Reproductive Health, and why does it matter for NEET?
a ~28-day hormonal cycle in which ovulation occurs around day 14, driven by FSH, LH, estrogen and progesterone.
What does “Restriction enzymes” actually mean in Biotechnology & its Applications, and why does it matter for NEET?
molecular scissors that cut DNA only at specific palindromic recognition sequences.
What does “Ten percent law” actually mean in Ecosystem & Ecology, and why does it matter for NEET?
only about 10% of the energy at one trophic level passes to the next.
Why is Euglena so difficult to classify as either a plant or an animal?
Euglena shows both sets of traits.
How do weak-stemmed climbers like peas and grapevines manage to grow upward?
Their stems can't stand on their own, so parts are modified into tendrils — slender, sensitive structures that coil around any support they touch (a response called thigmotropism).
How does a plant grow taller and also thicker — is it the same tissue doing both?
No, two different meristems do the two jobs.
Why can adding too much fertiliser actually 'burn' and kill a plant?
Roots absorb water by osmosis, which flows from the dilute soil into the more concentrated root cells.
Why does a potted plant on a windowsill bend and grow toward the light?
Light causes auxin to move to the shaded side of the shoot tip.
Why does a body become stiff (rigor mortis) some hours after death?
Detaching a myosin head from actin to relax a muscle requires ATP.
How can bananas and some grapes be seedless if seeds come from fertilisation?
These fruits form by parthenocarpy — fruit development WITHOUT fertilisation.
Where do antibiotics like penicillin actually come from?
Many antibiotics are made BY microbes to fight other microbes.
A woman of blood group AB marries a man of group O. What groups can the children be, and why never AB or O?
The AB mother contributes either I-A or I-B; the O father (ii) contributes only i.
In the lac operon, why are the lactose-digesting enzymes made only when lactose is present?
Normally a repressor protein sits on the operator and blocks transcription, so no enzymes are made.