Material Description:
Examples of monocotyledons and dicotyledonous seeds (corn, kidney beans), and spouted examples and dishes, chopping board, tissue paper, needle for pointing.
Method:
Oral Introduction
Say, ‘Remember when we cut open the fruit, what did we find inside (seeds) the seed is going to be the new plant, so the mother plant has to give it everything it needs, lets have a look at this seed’.
Take a kidney bean (dicotyledon) placed in a jar of water to soften. Try to push the seed out of it’s waterproof coat using your nail, (testa) and the outer shell (the cotyledons) place it into a small (dish 1, left).
‘In between these pieces we have the tiny, little, miniature plant’. Show the seed, say, ‘This is the baby plant called the embryo’, if possible identify the root and the stem. place it into a small dish (dish 2, right).
‘These are the two cotyledons, they are the food sacs for the embryo. I want to have a closer look at the embryo to see it’s parts.’
Take another kidney bean and split it with your nail.
In between the cotyledons we have the embryo, it is made up of the larger radicle which grows into the root, from the Latin ‘radicule’ meaning small root and the smaller plumule which develops into the shoot from the Lain ‘pumula’ meaning small feather. Let’s see if we can separate them. (dish 3, left)
Take another kidney bean and split the radicle and plumule. Place this into the final dish and explain that the waterproof coat is called the testa. (dish 4, right)
After the lesson:
The children take apart many kids of seed.
Types of seed
Material Description:
Chart P
Method:
After much experimentation with dissecting seeds the children will have noticed many new things, discuss this now.
There are two types of seed, seed with one food sac, called ‘monocotyledons’ they have one food sac and others with two food sacs, called dicotyledons.
- Monocotyledons are those plants with one food sac, parallel venation, fasciculated roots and flowers which are arranged in threes or multiple of three.
- Dicotyledons have reticulate venation, tap roots and flowers with petals arranged in groups of four or five.
Show Chart P, read the chart with the children, the character drawn has one sac
After the lesson:
The children do their own research
Simple Classification Exercise
Material Description:
Plants in the room, nomenclature cards for dicotyledons and monocotyledons, identification books
Method:
Invite the child to take plants from the environment and classify them.
Help the child to classify them using books
Notes:
Trees with concentric circles are dicotyledons, as are cactuses, orchids are monocotyledons.
Scattering the Seed
Material Description:
Charts P and Q
Method:
Looking at the chart say, ‘What is happening here? The mother is sending the seed off into the world, one of the important jobs for the mother plant is to see that it has everything it needs to grow and travel. It needs to grow, travel and find the right conditions. When some plants are ready to grow into new plants their fruit smells delicious and some very kind animals help to carry their seeds, the animal eats the fruit., the seed is swallowed and after a little while the seeds pass through the animals body and are dropped with manure to make the new plant. Other animals simply drop their seeds to make a new fruit. Some seeds that aren’t so delicious are given wings to fly. Other seeds don’t want any help from the animals, wind or human beings, they explode and shoot their seeds in many directions when they are ready to grow into a new plant. Other seeds use the water, like the coconut which travels along the top of the water, with a waterproof coat with a little hole in which lets in just enough water so that when it gets to land it is ready to grow into a new plant. Others stick onto peoples clothes and animals fur by burs, little hooks, after a while the person or animal shakes off the seeds in a new place’.
Show Chart Q
Describe it, ‘We can see seeds which travel on the wind, travel through the air, explode, travel on water and ones which travel on animals body’.
After the lesson:
Exploration in nature, using the nomenclature material
Collecting seeds, sorting them and putting them into different labelled containers
Children can mount seeds on cards to display them.
Aim:
This brings together all of the work done in botany so far.
Note:
Encourage limited collection to demonstrate ecological concern.
Follow up work:
Nine to twelve year old children can do projects on the various means used by the plant to ensure that the seed is scattered. Using the scientific term ‘seed dispersal’.