Biology
Briefly explain the following:
(i) Osmosis
(ii) Allele
(iii) Pulse
(iv) Reflex action
(v) Synapse
Roots Absorption
ICSE 2012
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Answer
(i) Osmosis — Osmosis is the movement of water molecules from their region of higher concentration (dilute solution or with a lower solute concentration) to their region of lower concentration (concentrated solution or with a higher solute concentration) through a semi permeable membrane.
(ii) Allele — Allele is one of the alternative form of the same gene responsible for determining contrasting characteristics.
(iii) Pulse — Pulse is the alternate expansion and elastic recoil of the wall of the artery during ventricular systole.
(iv) Reflex Action — Reflex action is an automatic or quick or immediate involuntary action in the body brought about by a stimulus.
(v) Synapse — Synapse is the point of contact between the terminal branches of the axon of a neuron with the dendrites of another neuron separated by a fine gap.
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