Why are some seeds of Citrus referred to as poly-embryonic ?

Why are some seeds of Citrus referred to as polyembryonic ?

Why is water referred as 'molecule of life' ?

Why is Kreb's cycle referred to as an amphibolic pathway?

If natural materials are pollutants, why do we not perceive their adverse effects during their their use ? When such materials are referred as pollutants ?

Why and how some spindle fibres elongate and some contract?

Why do new batteries 'become useless after some days?

Why some reactions of glycolysis are reversible and some irreversible.

Why are some substances are conductors while others are insulators?

Why are farmers and gardeners advised to buy new F_1 hybrid seeds every year ?

Why some people feel their ears popping at the top of a mountain.