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In a certain plant species which is normally green, a recessive gene for colour (n) causes the plants to be white in colour. Such plants die at an early age. In the heterozygous state, the plants are pale green in colour but grow to maturity.
(a) Give a reason for the early death of the
plants with homozygous recessive gene.
(b) If a normal green plant was crossed with pale green plant, what would be the genotype of the first filial generation (F1 generation)? Show your working.
(c) If heterozygous plants were self-pollinated and the resulting seeds planted, work out the proportion of their offspring that would grow to maturity.