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Definition:
In seed biology, double fertilization results in the growth of the endosperm and embryonic stem. Double fertilization occurs when two male gametes in the pollen grain fuse have two different parts of the ovary. Endosperm plays an important role in supporting embryonic growth. It provides nutrients, protects the fetus, and regulates embryonic development by acting as a barrier to seed germination and germination.
Development of endosperm and embryo
The egg that is inside the ovary of a flower contains the female gametophyte or the embryo. This sac contains the female gamete (egg yolk) as well as the central cell as well as other cells that are not essential for the development of the endosperm and embryo. Both of these are part of the seed in angiosperms.
The pollen grains are made up of two male gametes. During the double fertilization, one of the male gametes meets the female gamete (gametes live haploid), leading to the formation of a zygote (diploid cell) and later as an embryo. This includes the small embryonic axis that when the seed sprouts from a plant.
One male gamete interacts with a central diploid cell leading to the formation of a nucleus of the triploid endosperm. The developing embryo receives its nourishment from the endosperm. Repeated division of mitotic cells causes the formation of endosperm and is three tissues. Recent studies have shown that the endosperm is able to sense the environment and produce signals to control fetal growth.
Definition of endosperm
The endosperm is the surrounding tissue that grows from the nucleus of the main endosperm. Endosperms can be diploid, triploid, and polyploid. These provide nutrients to the embryo.
Definition of embryos
The embryo refers to the initial stage of growth of the multicellular diploid organism. In seeds such as angiosperms and gymnosperms, the embryo grows inside the seed.
The embryo carries an embryo, such as the umbilical cord, which grows on the root and plugs, which later grow into roots and sprout.
Basic features of the endosperm and embryo
- The endosperm provides nutrients for the development of plant embryos. In angiosperms, the endosperm is triploid, and in gymnosperms, haploid.
- During germination, the embryo secretes starchy signals as a food reservoir and promotes endosphere fitness.
- The endosperm is found mainly in monocot seeds while dicot seeds are replaced by cotyledons.
- The outer layer of the endosperm is called the aleurone layer in monocot seeds. This layer produces an amylase enzyme, which helps to break down starch into sugars for use in the fetus.
- The growing plant gets its food from the endosperm when it is a monocot seed while it is a dicot seed the growing plant receives nourishment from the cotyledons.
- The endosperm contains several hormones such as cytokines that help to differentiate cells and embryonic growth.
- Coconut water is an example of a liquid endosperm.
Development of endosperm and embryo classification
Endosperms are an important part of the offspring. Endosperm forms surrounding tissues that provide basic nutrients and nutrients to the developing foetus. The endosperm and embryo are further subdivided into subunits.
Types of endosperm
Based on development, the endosperm is of three types:
- Nuclear endosperm: This is a common form of endosperm development, in which nucleus fragmentation occurs repeatedly without the formation of cell walls (cytokinesis). It forms many free nuclei in the center cell of the embryo sac, pushing all the nuclei into the peripheral cytoplasm. Finally, cell wall formation occurs from the border to the center leading to the formation of multicellular endospermic tissue. Examples of nuclear endosperm are commonly found in coconut, corn, rice, wheat, cotton, and sunflowers, to name a few.
- Cellular Endosperm: In this type of endosperm development, each cell division of the main endosperm nucleus follows the formation of a cell wall. It involves the division of the nucleus of the endosperm into several parts, usually not interconnected. Such progress is rare. Examples of cellular endosperm are commonly found in petunia and datura.
- Global endosperm: This development is often associated with monocot fetal growth. This development is a combination of both cellular and nuclear. The process involves the formation of a cell wall following the breakdown of the original cells, similar to the development of cellular endosperm. However, subsequent disintegration does not lead to the formation of cell walls. Instead, it forms a large micropylar cell with additional divisions similar to nuclear endosperm. Examples of global endosperms are often found in foxtail lilies.
Types of embryos
Embryogenic, or embryonic stem form the diploid zygote, is of the following two main types:
- Dicotyledons – This is a type of development in which the apex is downward or present in the inner part of the zygote. The first part produces the basal cell toward the micropylar and the killer cell toward the chalaza. Dicots have two cotyledons present within them. Examples of dicot seeds are beans, peas, and mangoes, to name a few.
- Monocotyledons – In monocot embryos, early growth is similar to dicot embryos. Later, dissociation occurs repeatedly in both groups near and in the middle. Examples of monocot seeds are grass, orchids, and bananas, to name a few.
Similarities between endosperm and embryo
- Endosperm and embryos are two different structures of seed biology that occur in angiosperms.
- Both come from a system called double fertilization.
- Two sperm nuclei of pollen grains are responsible for double fertilization.
Differences between endosperm and embryo
- The endosperm provides nutrients and nutrients to the embryo of a growing plant in angiosperms. The embryo is a component of the seed that grows into a new kind of person.
- Endosperm occurs in angiosperms, and the embryo develops from all living cells that meet with fertilization.
- The endosperm and embryonic stem grow in triplicate fertilization and fertilization, respectively.
- The endosperm is a triploid to angiosperms, and the embryo has a diploid.
Endosperm and embryos are important parts of the seed and are responsible for germination. Endosperm in sperm is developed as a result of the triple bonding of the male gamete with the inner cell of the fetus. On the other hand, the embryo develops by being fertilized by all living organisms that have many reproductive cells. It grows when the male gamete meets an egg yolk in the ovary. Endosperms provide nourishment and nourishment for the developing embryo. There are three main types of endosperm and two major types of fetal growth. Endosperms are usually present in grains such as corn, wheat, and coconut.
Also read: Important Topic Of Biology: Fertilization
FAQs
Does endosperm and embryonic development occur simultaneously?
No, the endosperm is developed before embryonic development. The endosperm is produced when the second male gamete pollen meets the central diploid nuclei during fertilization. It provides food and nutrients to the developing fetus.
Do gymnosperms have endosperms and embryos?
Yes, gymnosperms contain both endosperm and embryos. But they do not have a real endosperm as the second male gamete of these two male gametes was destroyed before being assembled.
How are embryos and endosperms formed in angiosperm?
In line with the development of the endosperm and embryonic definition, two male pollen gametes interact with the female gamete and the central diploid nuclei, respectively, thus producing the zygote and the triploid endosperm.
