Seed dormancy is caused by the presence of . . . . . . .

Explain the methods to overcome seed dormancy.

What are seeds called that show tolerance to moisture and temperature reduction?

Which of the following is not a man-made method to overcome seed dormancy?
$(I)$ Seed coat broken by using knives,sandpapers,etc.
$(II)$ Passage of seed through the digestive tract of animals.
$(III)$ Effect of inhibitory substances can be removed by subjecting the seeds to chilling conditions.
$(IV)$ By application of certain chemicals like gibberellic acid and nitrates.

Legume seeds exhibit dormancy because of

In $Nigella$,what is the effect of light on seed germination?