Question

In Maize, a tubular sheath covers the plumule, it is
A. Coleoptile
B. Coleorhiza
C. Mesocotyl
D. Scutellum

Answer 1

Hint: In order to arrive at the correct answer, you must first know the parts of the maize grain. The parts of the maize grain are namely aleurone layer, endosperm, scutellum, coleoptile,coleorhiza,embryo and radical respectively. The coleoptile and the coleorhiza have fairly similar functions.

Complete answer:
1.Coleoptile-It is a protective covering that covers the emerging shoot especially in monocotyledons.
2.Coleorhiza-It is a special layer of tissue that covers the root present in the seed. It is the first part that grows out from the seed and is also known as the root sheath.
3.Mesocotyl-It is a white, stemlike and tube like structure especially a tissue that acts as a connection between the base of the coleoptile and the seed. It is referred to as the first internode of the stem.
4.Scutellum-It is also known as the seed leaf or a modified cotyledon.In maize it primarily stores food and also plays an important role in endosperm digestion during germination.
Maize grains derive their color from different pigments found in them. In yellow maize grain this color is generally derived from the pigments zeaxanthin and lutein respectively. However, the coloration of the kernel of corn is due to the presence of pigments like anthocyanins. These are synthesized in the flavonoid synthetic pathway and occur due to expression of the maize pericarp color 1 gene.

Thus, the correct option is option A Coleoptile.

Note:
The maize was first domesticated by the Mexican people. It is a cereal grain. It is the most important crop that is found in the Saharas in Africa and is a staple food to many farmers. The word maize comes from the native word Taino that means life giver.