What are 'true breeding lines' that are used to study inheritance pattern of traits in plants?

Variations caused by mutation, as proposed by Hugo de Vries are

• random and directionless

• small and directional

• small and directionless

• random and directional

In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F₁ generation pink flowers were obtained. When pink flowers were selfed, the F₂ generation showed white, red and pink flowers. Choose the incorrect statement from the following :

• Pink colour in F₁ is due to incomplete dominance.

• Ratio of F₂ is $\frac{1}{4} \left(\mathrm{Red}\right) : \frac{2}{4} \left(\mathrm{Pink}\right) : \frac{1}{4} \left(\mathrm{White}\right)$

• Law of segregation does not apply in this experiment

• This experiment does not follow the Priniciple of Dominance

What is the genetic disorder in which an individual has an overall masculine development gynaecomastia, and is sterile ?

• Klinefelter's syndrome

• Edward syndrome

• Down's syndrome

• Turner's syndrome

The frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes was explained by :

• Gregor J. Mendel

• Alfred Sturtevant

• Sutton Boveri

• T.H. Morgan