A homozygous tall plant (T) bearing red coloured (R) flowers is crossed with a homozygous dwarf (t) plant bearing white (r) flowers:
State Mendel’s law of Independent Assortment.
Topic: Law of Independent Assortment
Answer
MENDEL’S LAW OF INDEPENDENT ASSORTMENT states that when two pairs of contrasting characters are considered together, the distribution of the alleles of one character into the gametes is INDEPENDENT of the distribution of the alleles of the other character.
The essential word is INDEPENDENTLY — one character is inherited without reference to the other.
THE EVIDENCE is in parts (ii) and (v) of this very question. If height and flower colour were linked, the F1 plant could produce only the PARENTAL gametes TR and tr, and the F2 generation could show only tall-red and dwarf-white. The appearance of Tr and tR gametes — and of TALL-WHITE and DWARF-RED plants in F2 — proves the two characters assorted independently, and 9:3:3:1 is the numerical expression of it.
Mendel’s three laws: DOMINANCE (only the dominant shows in a hybrid), SEGREGATION (the two alleles of a pair separate into different gametes), INDEPENDENT ASSORTMENT (different pairs are inherited independently).