What does a seed need to germinate? Germination What does a seed need to germinate?

Structure of a seed Inside a seed you find an embryo plant which is attached to one or two seed leaves. The proper name for a seed leaf is a cotyledon There are two main groups of plants – those that have one seed leaf and those that have two. What might be inside the seed leaf?

What conditions are needed for germination? Light Dry Wet Dark

The stages of germination

How do plants reproduce? Seed dispersal How do plants reproduce?

Plantlet reproduction Spider plants, amongst others, send out stems which produce plantlets, these baby plants then try to root themselves

Acorns fall from the tree and sprout If they are not destroyed by animals, white oak acorns can sprout rapidly after falling from the tree. 

Animal dispersal by hooked fruits Some species of plant use hooks on their fruits to attach themselves to the fur of mammals or feathers of birds

Animal burial Hard nuts are usually destroyed if chewed or eaten. However, animals such as squirrels may store them to eat later and forget to go back to get them, giving them a chance to germinate.  On rare occasions, birds such as blue jays can transport acorns long distances.

Soft fruit dispersal Fleshy fruits The seeds of many plants are dispersed after passing through the digestive system of animals that have eaten the fleshy fruits. 

Wind dispersal Some plants, such as the dandelion, have seeds that act as parachutes, which are carried away by the wind

Spinning dispersal Maple fruits are winged, two-seeded pods.  They spin like helicopters as they fall from the tree, providing a longer time for dispersal by wind.

Exploding seeds Some seed pods dry out and then explode shooting the seeds over long distances

Shaking Some seed pods are a bit like a pepper pot. The wind shakes the seeds out.

Seed helicopters

Which length of wings makes the best seed helicopter?