What is the process of seed germination?
Seeds have three main parts:
- Seed coat
- Food storage (cotyledon)
The embryo is an immature plant that will grow to become an adult plant.
The seed coat is the protective outer covering.
Food store consists of starch, this is for the young plant to use until it’s able to carry out photosynthesis.
What is germination?
Germination is the process in which the seed begins to develop into a new young plant. This process is controlled by enzymes. There are a few factors required for the plant to grow.
The factors are:
- Warm temperature
The process of germination requires sunlight, water, oxygen, and warm temperature. The water required comes from the soil. Oxygen is required for aerobic respiration. Warm temperature increases enzyme activity and, ultimately the growth rate of the plant.
The process of germination begins when a seed is put into the soil. The seed begins to absorb water as it does this, the seed coat becomes soft and swells. The seed also requires nutrients which it gets from its food storage in the cotyledons. After this, the seed ruptures and begins to grow roots and shoots. The root grows into the soil to search for more water and nutrients. The root also helps to keep the seed anchored in place, then the shoot grows upwards through the soil towards a source of light and air. The seed coat falls off during the process. As the plant continues to grow it will need plenty of air, water, light, nutrients, and enough space to grow. The reason the plant needs all of these things is that it will need to carry out the process of photosynthesis.
Photosynthesis is the process in which carbon dioxide, water, and light energy produce oxygen and glucose. Once the roots and shoots are big enough to carry out the process of photosynthesis. The cotyledon falls off and becomes part of the soil. The plant then begins to grow leaves, flowers, and fruit.
What is the process of pollination and fertilisation?
Flowers are an important part of a plant.
They are the reproductive organs of a plant in which pollination and fertilisation.
What are the parts of a flower?
Parts of a flower:
The petals help to protect the parts of the flower. They are usually brightly coloured and have a nice scent.
The sepals are the parts of the plant that help to protect an unopened flower. Once the flower blooms, the sepal opens up.
Anther and filament
The anther and filament make up the male part of a flower called the stamen. The stamen consists of anthers that are held up on filaments. Anthers produce pollen grains which are vital for the process of pollination and reproduction of the plant.
Stigma, style, ovary & ovules
The stigma, style, ovary, and ovules make up the female part of a flower called the pistil.
The stigma is the top of the female part of the flower. This is involved in collecting the pollen grains. A pollen tube grows through the style until it reaches the ovary. The pollen tube then fuses with the nucleus of the ovule to complete the process of fertilisation.
What is pollination?
Pollination occurs first. This is the process in which pollen from one plant is transferred onto the stigma of another plant.
Pollination can occur in a few different ways. Insect pollination is where an insect carries pollen from one flower to another flower. These insects are attracted to the bright-coloured petals, and the nice smell. The pollen sticks to the insect, and it’s carried all the way to another flower, where the pollen sticks to the stigma. Pollination can also occur by wind and water, so this is where the wind or the water carries the pollen to another flower.
What is plant fertilisation?
Plant fertilisation is the process in which the male and female gametes are fused together in order to produce a fertilised egg. The pollen that is transferred to another flower stigma initiates the process of fertilisation.
Once the pollen grains have been transferred onto the stigma, a pollen tube grows through the style until it reaches the ovary. Inside the ovary, the nucleus of the pollen passes along the tube and fuses with the nucleus of the ovule.
This is when the process of fertilisation is complete. Once fertilisation is complete, the ovules become seeds, and the rest of the carpel becomes a fruit. The petals of the flower die in this process, for example, an apple that contains seeds inside. It is important to remember that some plants can reproduce without pollen or an egg.