Why is seed dispersal important? By group SEEDS (10) P5E •It What is seed dispersal? is the way seeds are dispersed. •There are many forms of seed dispersal. •Seed dispersal makes sure that overcrowding does not happen •It also enables a species of plant to flourish in various areas. Methods of seed dispersal.(to be continued…) •By gravity > Barochory •In Barochory, the fruit drops onto the floor when ripe, dispersing the seeds. (eg. Apples) •By animals > Zoochory •In Zoochory, the seeds have hooks to hook onto animals fur. (eg. Bur) Another kind of Zoochory is when an animal eats a fruit, and the seeds get passed out through its faeces. (eg. Cherries) More methods of seed dispersal. •By the wind > Anemochory •In Anemochory, seeds are light and/or have wing-like structures. (eg. Dandelion) •By water > Hydrochory •In Hydrochory, the fruit, often still with the seeds inside, have fibrous husks to enable them to float on water. (eg. Coconut) Advantages and disadvantage of dispersal Advantages and disadvantage of seed dispersal Wind Advantage: It will go further from parent plant and avoid overcrowding . Disadvantages: It will reduce the chance of survival for the seed as if it floats to a place without soil, it cannot germinate How wind dispersal works- works when the wind blows and it carries away the pollen of dome plants. Some plants like mosses and ferns rely on the wind to help them carry their pollen from one place to another. Dandelions have small wing on their seeds helping to be easily get carried away by the wind from one place to another A video of wind dispersal Explosive Explosive splitting enables the seed to be dispersed only around the parent plant, and not as far as other methods of dispersal, such as animal dispersal, of which the seeds can be dispersed for as many as a few kilometers. Exploding seed pod video Animal It furthers distance traveled by the seeds, helps avoid inbred-depression and expands gene pool Pollinating animals are attracted to prominent and colorful flower petals. Similarly, modified fruits such as burs may cling to animal hair, which can deposit seeds miles away. Reproduction of plants Summary WIND LIGHT Feather/wing like structure Wings are twisted and balanced Eg. Dandelion.. WATER WATERPROOF FIBEROUS HUSK WHICH HELPS FLOAT ON WATER Eg. Coconut, lotus… ANIMAL EXPLOSIVE MECHANISM “Hooks” which hook onto the animal Dry pods Undigesta ble seeds. Colourful and fleshly.(Edi ble) Eg. Apples… Eg. Balsam… http://www.you tube.com/watc h?v=O6afGgZrn nA&feature=rel ated The story of Rice (rice seed) Here is an olden myth about rice… Long ago, in an ancient land, there lived the Rice tribe. One day ,the locals met a few people in white. They gave them a few seeds and disappeared. The awestruck locals planted the seeds, and the next day, rice plants sprouted. Since then, people all over the world have eaten rice. It’s…. TIME!!! Exciting prizes to be won! (Terms and conditions apply) 1. Name 3 plants that disperses its seeds by wind? Answer> Shorea, lalang, dandelion, angsana (any 3) 2. Briefly explain why seed dispersal is important. Answer> It prevents over crowding./ It enables the same species of plants to flourish in different regions. 3. Name the specific name of seed dispersal by gravity. Answer> Barochory 4. Name the characteristics of seeds that are dispersed by wind. Answer>Light, wing/feather like structures, twisted and balanced. Sources… •www.wikipedia.com •www.google.com •www.yahoo.com •www.youtube.com !!!!! Group Members •Ryan Ng (Leader) •Xavier Chia (ICT Leader) •Victoria Tham •Kalyani S. Anil Special Thanks •Mdm Arunah •Miss Wong •Members of Temasek Primary’s IT Resource Room THANK YOU!!!