Q.72 During the germination of cereal seeds, what is the role of a-amylase present in the
aleurone layer?

1. It directly gets converted into sugars
2. It is a reserve food material
3. It hydrolyzes the endosperm starch into sugars, which provide the energy for
the growth of roots and shoots
4. It is responsible for seed dormancy

Role of α-Amylase in Cereal Seed Germination

α-Amylase in the aleurone layer is essential for breaking down stored starch during cereal seed germination, enabling embryo growth. This SEO-optimized article covers the correct answer, all options, and the biology behind it for students and researchers.

Correct Answer

Option 3: It hydrolyzes the endosperm starch into sugars, which provide the energy for the growth of roots and shoots.

During germination, gibberellins from the embryo signal the aleurone layer to synthesize and secrete α-amylase. This enzyme then hydrolyzes starch in the endosperm into maltose and glucose, fueling root and shoot development until photosynthesis begins.

Option Analysis

Option 1: It directly gets converted into sugars

α-Amylase is an enzyme, not a substrate, so it does not convert into sugars. Instead, it catalyzes starch breakdown externally in the endosperm.

Option 2: It is a reserve food material

Reserve food like starch resides in the endosperm, not the aleurone where α-amylase is produced. The enzyme mobilizes these reserves, but is not food itself.

Option 3: Correct (Detailed Above)

This matches the precise role: starch hydrolysis provides energy via simple sugars for embryonic growth.

Option 4: It is responsible for seed dormancy

Seed dormancy involves abscisic acid inhibiting α-amylase; gibberellins counteract this to promote germination. α-Amylase aids breaking dormancy, not causing it.