Part 5: Plant reproduction
6. Storage tissues
The endosperm in the seed is a store for energy that allows the seed to grow and the seedling to develop to the point that it can feed itself from its roots.
Endo = ‘within’
Sperm = ‘seed’
Endosperm = ‘within seed’
What is in the endosperm?
- Starch
- Protein
- Sometimes oils and fats.
Some tiny, dust-like seeds have no endosperm.
Substrate breakdown in the endosperm
Enzymes in the seed, which become active when the seed imbibes water, break down the large storage molecules of starch in the endosperm and cotyledons into smaller molecules of glucose which can be used for respiration to produce energy for growth. Specific enzymes which loosen the cell wall are also produced during this phase of germination to prepare for the radicle to emerge from the seed.