3.5: Practical: Understand the Conditions Needed for Seed Germination

GERMINATION: Process by which Seed emerges from period of dormancy and begins to sprout

CONDITIONS NEEDED FOR SEED GERMINATION:  

FEATURE	EXPLANATION
WATER	Water is needed to metabolically activate enzymes to break down food reserves of Starch into Glucose (source of energy for growth)
OXYGEN	Oxygen is needed for aerobic respiration to produce energy in the form of ATP for growth
WARMTH	]Optimum temperature is needed for optimal enzyme activity to facilitate survival and growth of Seed

INVESTIGATING GERMINATION

Diagram showing the Experiment to Investigate Factors that affect Germination

METHOD: s Cotton wool is placed at the bottom of four boiling tubes, each containing five Cress Seeds Each test tube is then individually set up: Test Tube A: moist cotton wool and placed in warm environment (hot water bath set at appropriate temperature) Test Tube B: dry cotton wool and placed in warm environment (hot water bath set at appropriate temperature) Test Tube C: moist cotton wool and is placed in cold environment (bucket of ice) Test Tube D: cotton wool soaked in boiled Water that is cooled off, and layered with Oil on top After all test tubes are set up, Cress Seeds in each respective test tube is allowed to adjust to new environment for a fixed number of days After a fixed number of days has passed, results are compared via: Number of Cress Seeds germinated Height of Germinated Seed

RESULT: TEST TUBE FACTOR BEING TESTED SEEDS GERMINATED A Control (All Factors Present) Yes B Water No C Temperature No D Oxygen No