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.

What is in the endosperm?

  • Starch
  • Protein
  • Sometimes Oils and Fats

Endo = ‘within’

Sperm = ‘seed’

Endosperm = ‘within seed’

During germination the embryo submits signals to the endosperm which causes it to start breaking down and releasing nutrients. The endosperm also breaks down structurally which allows the cotyledons to emerge from the seed.

The endosperm is able to recognise environmental signals and it can give signals to the embryo to regulate its growth according to the environment around the seed.

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. The large molecules are broken 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.

Advanced reading activity:


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