Life cycle of a Flowering Plant
Review:
- Plants can be group into Flowering and Non-flowering Plants.
- Flowering Plants have flowers and reproduce by seeds.
- Non-flowering Plants do not have flowers and reproduce by spores.
We will learn in this chapter about the life cycle of flowering plants.
(life cycle of non-flowering plants is not in the syllabus)
Watch how this green bean plant grows first before we begin our discussion on the life cycle of flowering plants...
What you should have noticed is that the seed, from a lifeless looking oval shaped bead, starts to soak up water.
After which, bursting its seed coat, it starts to grow its root FIRST.
The root grows downwards, no matter what position the seed is placed.
After the seed has anchored its root, we can see the little seedling growing its shoot upwards NEXT.
The two parts that you see rising up together with the shoot is known as the seed leaves.
They are not leaves, but are nutrient-filled parts which provide the seedling with the necessary food for growth BEFORE it has leaves to make its own food.
As you will actually observe if you do this experiment, the seed leaves (not the green ones) will eventually start to shrink and drop off.
This is because the plant has used up the nutrients within it and has developed green leaves capable of making its own food.
At this stage, the seedling has become a young plant which will grow up to mature, produce flowers and bear fruits and seeds to continue the life cycle.
After which, bursting its seed coat, it starts to grow its root FIRST.
The root grows downwards, no matter what position the seed is placed.
After the seed has anchored its root, we can see the little seedling growing its shoot upwards NEXT.
The two parts that you see rising up together with the shoot is known as the seed leaves.
They are not leaves, but are nutrient-filled parts which provide the seedling with the necessary food for growth BEFORE it has leaves to make its own food.
As you will actually observe if you do this experiment, the seed leaves (not the green ones) will eventually start to shrink and drop off.
This is because the plant has used up the nutrients within it and has developed green leaves capable of making its own food.
At this stage, the seedling has become a young plant which will grow up to mature, produce flowers and bear fruits and seeds to continue the life cycle.
Seed
The seed before it reaches this stage, requires 3 main things to germinate (start its growth)
1. Air
2. Water
3. Warmth (the seed cannot grow if the temperature of its surroundings is too cold. E.g in a fridge)
It is commonly misunderstood that a seed needs soil to grow. This is not true. Humans have found a way to grow plants without soil. Hydrophonics is a way in which plants are grown using a nutrient rich solution.
The seed that germinates is then called a seedling.
The seed before it reaches this stage, requires 3 main things to germinate (start its growth)
1. Air
2. Water
3. Warmth (the seed cannot grow if the temperature of its surroundings is too cold. E.g in a fridge)
It is commonly misunderstood that a seed needs soil to grow. This is not true. Humans have found a way to grow plants without soil. Hydrophonics is a way in which plants are grown using a nutrient rich solution.
The seed that germinates is then called a seedling.
Seedling
The seedling cannot make food without green leaves, so it gets its food from the nutrients stored in the seed leaves.
When its first green leaves appear, then it is able to make its own food.
By then, the nutrients would have been used up and the seed leaves would shrink and drop off.
Observe the pictures of the seed leaves below:
The seedling cannot make food without green leaves, so it gets its food from the nutrients stored in the seed leaves.
When its first green leaves appear, then it is able to make its own food.
By then, the nutrients would have been used up and the seed leaves would shrink and drop off.
Observe the pictures of the seed leaves below:
Seed leaves
images taken from: www.oldschool.com.sg
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The view of a seed when split into two.
image from: http://scienceprint.com
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Young Plant (with green leaves)
As the green leaves form, the plant is able to make its own food.
The roots grow deeper and start stretching out further in search of water and mineral salts.
Adult plant
Once the plant has successfully grown more leaves and has reached maturity, it will produce flowers.
When the flowers have been fertilized and becomes fruit, the seeds are dispersed and the life cycle continues as the seeds grow.