Importance of fertilization

  1. Embryo Development: Fertilization results in the formation of a zygote. The zygote divides to form the pro-embryo. The embryo divides to become a complete embryo. The primordial embryo divides to form the complete embryo through cotyledons, embryos and root formations.
  2. Origin of seeds: The main source of food in the living world is seeds. The sperm unites with the secondary nucleus to form the endosperm or seed.
  3. Seed production: Zygote is formed by the union of sperm and egg. After the zygote is formed, the ovum develops into a seed.
  4. Fruit formation: After fertilization, the ovary of the flower gradually turns into fruit and the skin of the ovary turns into fruit.
  5. Reproduction: After the union of sperm and egg, the ovule of the flower turns into a seed. Most plants on Earth reproduce by seeds.
  6. Formation of new species: Zygote is formed by the union of two different cells sperm and egg. It gives rise to new species with new characteristics.
  7. Creation of Biodiversity: Zygote is created by the union of sperm and egg. New species are formed from the zygote. Biodiversity is created through new species.
  8. Fulfillment of food needs: Seeds and fruits are created through fertilization. Seeds and fruits fulfill the food needs of living organisms. Mango, yam, jackfruit, litchi, papaya, bell, palm, paddy, wheat, bhutra, barley, cown etc. meet the food needs.
  9. Creation of disease-resistant varieties: Through fertilization, disease-resistant varieties of plants can be created.
  10. Development of desired characteristics: Development of desired characteristics of plants can be done through fertilization.
  11. Evolution: Neshik plays an important role in describing the course of evolution.
  12. Chromosome balance: In the process of fertilization, a diploid zygote is formed by the union of sperm and egg. It keeps the number of chromosomes of the organism constant.

Fertilization steps of plant

The process by which female gamete and male gamete are sexually united is called fertilization or fertilization. Sexual reproduction of herbaceous plants is ugamous in nature. The stages of fertilization process are described as-

  1. Pollen Germination: Inside the anther, the pollen nucleus divides to form two nuclei. Tubular nucleus and gonial nucleus. In the binucleate state, the pollen grains fall into the female endosperm through pollination. Pollen is trapped in the endosperm by the sticky sap secreted by the endosperm or with appendages. Pollen enlarges by absorbing fluid. This condition is called hydration. The anther is energized and pressure builds up inside it. Due to this pressure, the integument of the pollen tube is extruded through the reproductive pore. It is called pollen tube. Pollen does not germinate without its own species.
  2. Pollen tube travel to the uterus and sperm production: Cutinase enzyme degrades the cutin of the uterus and the pollen tube enters the uterus. Enzymes like pectinase, cellulase etc. are secreted from the tip of the pollen tube and dissolve the pistil cells to form the tube. The pollen tube continues towards the ovary under the influence of calcium (Ca++) ions released from the ovary and ovary. The tube nucleus enters the pollen tube first and the generative nucleus later. The germ nucleus divides to form two spermatozoa.
  3. Entry of the pollen tube into the embryo sac: The pollen tube enlarges and reaches the uterus. Penetrates the lining of the uterus and enters the ovum. The membrane of the ovary dissolves and the anther approaches the ovule. In most plants the pollen tube enters the ovary through the ovule.
  4. Ejection of sperm into the ovary: After the pollen tube enters the ovary, its tip bursts. Through the slit, the sperm enters the two follicles.
  5. Union of sperm and egg: In the embryo sac, one of the sperm moves towards the egg and the other towards the secondary nucleus like an amoeba. One of the two sperm fuses with the egg and the other fuses with the secondary nucleus. The union of sperm and ovum is called fertilization or syngamy and the union of sperm and secondary nucleus is termed triunion. Nishek and Trimilan together are called Bi-Nishek.

Fertilization process of plants

The process by which female gamete and male gamete are sexually united is called fertilization or fertilization. Sexual reproduction of herbaceous plants is ugamous in nature. The stages of fertilization process are described as-

  1. Pollen Germination: Inside the anther, the pollen nucleus divides to form two nuclei. Tubular nucleus and gonial nucleus. In the binucleate state, the pollen grains fall into the female endosperm through pollination. Pollen is trapped in the endosperm by the sticky sap secreted by the endosperm or with appendages. Pollen enlarges by absorbing fluid. This condition is called hydration. The anther is energized and pressure builds up inside it. Due to this pressure, the integument of the pollen tube is extruded through the reproductive pore. It is called pollen tube. Pollen does not germinate without its own species.
  2. Pollen tube travel to the uterus and sperm production: Cutinase enzyme degrades the cutin of the uterus and the pollen tube enters the uterus. Enzymes like pectinase, cellulase etc. are secreted from the tip of the pollen tube and dissolve the pistil cells to form the tube. The pollen tube continues towards the ovary under the influence of calcium (Ca++) ions released from the ovary and ovary. The tube nucleus enters the pollen tube first and the generative nucleus later. The germ nucleus divides to form two spermatozoa.
  3. Entry of the pollen tube into the embryo sac: The pollen tube enlarges and reaches the uterus. Penetrates the lining of the uterus and enters the ovum. The membrane of the ovary dissolves and the anther approaches the ovule. In most plants the pollen tube enters the ovary through the ovule.
  4. Ejection of sperm into the ovary: After the pollen tube enters the ovary, its tip bursts. Through the slit, the sperm enters the two follicles.
  5. Union of sperm and egg: In the embryo sac, one of the sperm moves towards the egg and the other towards the secondary nucleus like an amoeba. One of the two sperm fuses with the egg and the other fuses with the secondary nucleus. The union of sperm and ovum is called fertilization or syngamy and the union of sperm and secondary nucleus is termed triunion. Nishek and Trimilan together are called Bi-Nishek.

Embryo sac-structure

The sac-like part inside the nucellus is called embryo sac. It contains embryos, protuberance cells and secondary nuclei.

(i) Embryos : The three cells near the oviduct of the embryo are collectively called the embryos. Among them, the large cell in the middle is called ovule and the smaller cells on both sides are called companion cells.

(ii) Antipodal cells: The three cells on the ovule side of the embryo are collectively called Antipodal cells.

(iii) Secondary Nucleus: Two nuclei from the two poles come to the center of the embryo and fuse to form the secondary nucleus.

Structure of ovule

  1. Ovary: The finger like part of ovary is called ovary. The ovule is attached to the amara by means of bota. In some species, the ovary and ovary are joined together to form raphe.
  2. Umbilical cord: The area of ​​the ovary where the ovary is attached is called the umbilical cord.
  3. Ovary: The membrane covering the ovary is called ovary. It has two levels. Epidermis and endodermis.
  4. Nucellus: The main part of ovule covered by ovule is called nucellus.
  5. Ovary: The root of the ovary is called the ovary.
  6. Oviduct: The opening at the tip of the ovary is called Oviduct. Sperm enters through this.
  7. Embryo sac: The sac-like part inside the nucellus is called embryo sac. It contains embryos, protuberance cells and secondary nuclei.

(i) Embryos : The three cells near the oviduct of the embryo are collectively called the embryos. Among them, the large cell in the middle is called ovule and the smaller cells on both sides are called companion cells.

(ii) Antipodal cells: The three cells on the ovule side of the embryo are collectively called Antipodal cells.

(iii) Secondary Nucleus: Two nuclei from the two poles come to the center of the embryo and fuse to form the secondary nucleus.