Seed Dispersal Lab

Dispersal by Water The coconut can float on water for long intervals due to an air-filled pericarp layer.

Dispersal by Water Mangrove seeds germinate while still attached to the adult plant. Seedlings are released into water.

Dispersal by Water When its seed pod breaks open, Pond Iris seeds fall into nearby water. Seeds can float for long distances and germinate either in the water or when they become lodged in mud.

Dispersal by Wind The feathery pappus helps carry the dandelion seed in an updraft. Seeds with wings have a slower descent when they fall from a tree.

Dispersal by Wind The Red Campion ovary produces a “pepper pot” seed capsule with openings at the top. Wind shakes the capsule to scatter the seeds.

Dispersal by Animals: Fleshy Fruits Persimmons Mulberries Animals eat the fruit and deposit the undigested seeds at another location.

Dispersal by Animals: Attachment The cockleburr fruit has hooked barbs for attaching to an animal’s fur or a bird’s feathers.

Dispersal by Animals: Attachment Mistletoe has a sticky fruit that attaches to the beak and faces of birds. Birds scrape their beaks on tree branches to spread the seeds.

Mechanical Dispersal The seeds are released when a ripe capsule of an Impatiens plant is touched.

Mechanical Dispersal A thick husk that splits open to release a hickory nut.

Today’s Lab Survey of Seed Dispersal Mechanisms Observe and draw seeds Propose dispersal mechanism Design and test a wind-dispersed seed Distance: Air stream test Time airborne: Balcony test

Worksheet Complete pages161-165 from lab manual Be sure your instructor checks your completed worksheet before you leave the lab