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Sexual Reproduction. Plants grow from seeds. These plants have parts that are responsible in the making of seed. These seed-making parts of plants are found in the flowers. The Pistil and the Stamen.
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Plants grow from seeds. These plants have parts that are responsible in the making of seed. These seed-making parts of plants are found in the flowers.
The Pistil and the Stamen The pistil and the stamen are parts of a flower that are responsible in the making of seeds in flowering plants.
The Stamen • The stamen is the male reproductive organ. It consists of a stalk called the filament and an ovoid structure at its tip called the anther. The anther bears the pollen grains.
The Pistil • The pistil is the female reproductive organ found at the center of the flower. It consists of the ovary, style, and stigma. An egg cell is formed in the ovule. The ovules, after fertilization, will develop into seeds and the ovary surrounding it becomes the fruits in most plants.
One of the function of the flower is to produce seeds. How???
Pollination occurs mainly by wind and by animals such as insects and birds
Self Pollination When pollen from plant’s anther is transferred to that same plant’s stigma is called self-pollination
Cross Pollination when pollen from a plant’s anther is transferred to another plant’s stigma, it is called cross-pollination.
Fertilization and Development of the Seed What is fertilization? How does fertilization in flower lead to the formation of seeds?
In order for fertilization to occur, sperm cells must be able to unite with eggs. The sperm cells of the flowering plants are contained in pollen grains. After the pollen lands on the stigma, a tube grows from the pollen. The tip of the tube breaks, releasing the sperm cells.
Fertilization occurs as one of the sperm cells unite with the egg inside the ovule. The union forms a new cell which develops into an embryo. The parts surrounding it change also, forming an outer coat and an inner part filled with food , the endosperm. The ovule consisting of the embryo, endosperm and coat becomes the seed. The ovary around the seed develops, forming the fruit.
