NEET 2004 · Class 12

Principles of Inheritance and Variation

Lack of independent assortment of two genes A and B in fruit fly Drosophila is due to

  1. (A)repulsion
  2. (B)recombination
  3. (C)linkage
  4. (D)crossing over

The NCERT line that answers it

Verbatim line

Morgan attributed this due to the physical association or linkage of the two genes and coined the term **linkage** to describe this physical association of genes on a chromosome and the term **recombination** to describe the generation of non-parental gene combinations (Figure 4.11).

Chapter
Principles of Inheritance and Variation
Section
4.3.3 Linkage and Recombination
Page
16
Words matched
43 of 43

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

8, emb=1.0, combined=0.92). Verified: high — The span explicitly states that Morgan attributed the lack of independent assortment to 'the physical association or linkage of the two genes' and defines linkage as 'this physical association of genes on a chromosome', which directly answers why genes A and B don't assort independently.

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