Fig. 7.4.9 Water lily seeds are dispersed by water
z
Fig. 7.4.10 Pea pods explode and scatter the peas
5. Germination Germination is the growth of a seed to form a new plant.
Plumule
Radicle z
After dispersal, seeds will germinate if the conditions are suitable. The conditions needed for germination are:
zz zz zz
Water Oxygen A suitable temperature
1. The seed coat splits and the radicle grows out and downwards into soil. The radicle will develop into the root.
2. Then the plumule emerges and grows upwards, which will develop into the shoot system.
3. Initially, the seed relies on its food store but once the shoot system breaks ground, the seedling can start to photosynthesise. The seedling is now independent and will continue to grow.
Investigating germination
Plan, design, carry out and write up an investigation to examine the factors that affect seed germination.
