The hollow foliar structure enclosing the shoot apex in monocots is:
Epicotyl has a shoot apex and a few leaf primordia enclosed in a hollow foliar structure, the coleoptile.
Question 132 of 501
📘 CLASS XII
Seed dormancy is triggered by:
As the seed matures, its water content is reduced... The general metabolic activity of the embryo slows down. The embryo may enter a state of inactivity called dormancy.
Question 133 of 501
📘 CLASS XII
A seed is essentially a:
In angiosperms, the seed is the final product of sexual reproduction. It is often described as a fertilised ovule.
Question 134 of 501
📘 CLASS XII
The oldest viable seed, Lupinus arcticus, was excavated from:
The oldest is that of a lupine, Lupinus arcticus excavated from Arctic Tundra.
Question 135 of 501
📘 CLASS XII
Parasitic species like Orobanche produce:
Similar is the case in fruits of some parasitic species such as Orobanche and Striga. (Referring to thousands of tiny seeds).
Question 136 of 501
📘 CLASS XII
Apomixis is observed in species of:
A few flowering plants such as some species of Asteraceae and grasses, have evolved a special mechanism... called apomixis.
Question 137 of 501
📘 CLASS XII
In Citrus and Mango, polyembryony arises from:
In many Citrus and Mango varieties some of the nucellar cells surrounding the embryo sac start dividing, protrude into the embryo sac and develop into the embryos.
Question 138 of 501
📘 CLASS XII
Hybrid seeds have to be produced every year because:
If the seeds collected from hybrids are sown, the plants in the progeny will segregate and do not maintain hybrid characters.
Question 139 of 501
📘 CLASS XII
A typical microsporangium appears ________ in transverse section.
In a transverse section, a typical microsporangium appears near circular in outline.
Question 140 of 501
📘 CLASS XII
Which layer of the microsporangium helps in dehiscence of anther?
The outer three wall layers perform the function of protection and help in dehiscence of anther.
