Enzyme Activation: Once water is absorbed, the seed produces enzymes like amylase to begin the breakdown of insoluble storage molecules.
Starch Mobilization: Insoluble starch is converted into soluble sugars through a multi-step process:
Energy Release: The resulting glucose is transported to the growing regions (meristems) of the radicle and plumule to be used in respiration:
Structural Growth: Some glucose is also converted into cellulose to build new cell walls as the seedling increases in size.
The 'Oil Layer' Trap: In experiments testing oxygen requirements, a layer of oil is often placed over boiled water. Remember that boiling removes dissolved oxygen, and the oil prevents it from re-entering.
Variable Control: When designing germination experiments, always ensure the seeds come from the same batch/species to maintain genetic consistency (the 'O' in CORMS).
Measurement Criteria: When asked how to measure germination, 'percentage of seeds sprouted' or 'length of the radicle' are more precise than just saying 'growth'.
Reasonableness Check: If a question asks why seeds in a fridge didn't grow, focus on enzyme kinetic energy rather than saying the seeds were 'killed' (unless frozen, they are usually just dormant).
The Light Myth: A common misconception is that all seeds require light to germinate. While some do, most seeds germinate underground in the dark, relying entirely on their internal food stores.
Water vs. Drowning: While water is required, complete submergence without aeration leads to 'drowning' because the seed cannot access the oxygen needed for respiration.
Dry Mass Confusion: Students often forget that a germinating seed actually loses dry mass initially because it is burning up its starch reserves to produce energy and CO2.
