What is asexual reproduction in science

what is asexual reproduction in science

Advantages and disadvantages of asexual reproduction in plants

Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of niceloveme.com offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the full set of genes of their single parent. Asexual reproduction is the primary form of reproduction for single-celled organisms such as archaea and bacteria. Asexual reproduction is a mode of reproduction in which a new offspring is produced by a single parent. The new individuals produced are genetically and physically identical to each other, i.e., they are the clones of their parent.

Both homosporous and heterosporous life histories may exhibit various types of asexual reproduction vegetative reproduction, somatic reproduction. Asexual reproduction is any reproductive process that does not involve meiosis or the union of nuclei, sex cells, or sex organs. Depending on the type of life history, asexual reproduction can involve the 1 whatt or 2 n generation.

The significance of sexual reproduction is that it is responsible for the genetic variation arising in a population as a result of the segregation and recombination of genetic material via meiosis and syngamy, respectively the cells that result from sexual reproduction are genetically different from their parent cells.

The significance of asexual reproduction is that it is a means for a rapid and significant increase in the numbers of individuals. Many weeds and invasive speciesfor instance, are successful partly because of their great capacity for vegetative reproduction. The cells that result from asexual reproduction are genetically identical to their parent cells. In addition, vegetative reproduction in the bryophytes and pteridophytes is a means of bypassing the somewhat lengthy and moisture-dependent sexual process; that is, the motile swimming sperm characteristic of these groups require the presence of water, which may be a limiting factor in drier times.

In most life histories, a 2 n sporophyte typically alternates with a 1 n gametophytebut there are significant deviations. Apospory is the development of 2 n gametophytes, without meiosis and spores, from vegetative, or nonreproductive, cells of the sporophyte.

In contrast, apogamy is the development of 1 n sporophytes without gametes and syngamy from vegetative cells of the gametophyte. The 2 n aposporous gametophytes and the 1 n apogamous sporophytes are usually infertile under natural conditions because of disruption of cytological events. Various compensating genetic mechanisms, however, may occur to complete the life history. Parthenogenesis is the formation of a 1 n embryo directly from an unfertilized egg.

Apospory and apogamy occur what is unit of analysis bryophytes, pteridophytes, and angiosperms, whereas parthenogenesis occurs in ferns and angiosperms.

Ni is more common in pteridophytes, but apospory is more common in bryophytes. Some ferns certain species of Trichomanes and Vittaria have lost the ability to produce sporophytes. The species exist as gametophytes that spread by gemmae units of asexual reproduction ; although gametangia are produced, no sporophytes result. Plant nutrition includes the nutrients necessary for the growth, maintenance, and reproduction of individual plants; the mechanisms by which plants acquire such nutrients; and the structural, physiological, and biochemical roles those nutrients play in metabolism.

All organisms obtain their nutrients from the environmentbut not all organisms require the same nutrients, nor do they assimilate these nutrients in the same way. There are two basic nutritional types, autotrophs and heterotrophs. Heterotrophs require both inorganic and organic carbon -containing asexjal as nutrient sources. Autotrophs obtain their nutrients from inorganic compounds, and their source of carbon is carbon dioxide CO 2. An autotroph is photoautotrophic if light energy is required to assimilate CO 2 reprodyction the organic constituents of the cell.

Furthermore, a photoautotroph that also uses water awexual liberates oxygen in the energy-trapping process of photosynthesis is an oxygenic photoautotroph. Almost all plants, as well as many prokaryotes and protistsare characteristically oxygenic photoautotrophs. Qhat, as autotrophic organisms, use asexuual energy to photosynthesize sugars from CO 2 and water. They also synthesize amino acids and vitamins from carbon fixed in photosynthesis how to be brooke davis from inorganic elements garnered from the environment.

Animalsas heterotrophic organisms, cannot synthesize many nutrients, including certain amino acids and vitamins, and so must take them from the environment. Certain key elements are required, or essential, for the complex processes of metabolism to take place in plants. Plant physiologists generally consider an element to be essential if 1 the plant is unable to complete its life cycle i.

Beneficial elements are those that stimulate plant growth by ameliorating the toxic effects of other elements or by substituting for an element in a less-essential role e. Some elements are beneficial in that they are necessary for the growth of some, but not all, plant species. The required concentrations of each essential and beneficial element vary over a wide range.

The essential elements required in relatively large quantities for adequate growth are called macroelements. Eight other essential mineral elements are required in smaller amounts 0. The specific required percentages may vary considerably with species, genotype or varietyage of the plant, and environmental conditions of growth. A macronutrient how to play table shuffleboard the actual chemical form or compound in which the macroelement enters the root system of a plant.

Carnivorous plants use nitrogen from the proteins and nucleic acids of the prey they catch. Carbon dioxide from the atmosphere provides the carbon and oxygen atoms. Water taken from the soil provides much of the hydrogen.

Soil provides macroelements and microelements from mineral complexes, parent rock, and decaying organisms.

Factors that determine plant root uptake include the solubility and mobility of the chemical in question, the adsorptive properties of the charged soil surfaces, and the surface area and uptake capacity of the roots of the individual plant. The macroelements carbon, hydrogen, oxygen, and nitrogen constitute more than 96 percent of what is asexual reproduction in science dry weight of plants.

Thus, they are the major constituents of the structural and metabolic compounds of the plant. Their presence reproductuon that of potassium within cells also helps regulate osmotic pressure.

In addition, phosphate is a what is dynamic link library of nucleic acids, including DNAand membranes ; it also plays a role in various metabolic pathways. Microelements are generally either activators or components of enzymes, although the macroelements potassium, calcium, and magnesium also serve these roles.

Metabolism denotes the sum of the chemical reactions in the cell that provide the energy and synthesized materials required for growth, whaat, and maintenance of structure and function. In plants the ultimate source of all organic chemicals and the rrproduction stored in their chemical bonds is the conversion of CO 2 into organic compounds CO 2 fixation by either photosynthesis or chemosynthesis. The general and specific features of plant metabolism ultimately derive from oxygenic photosynthesis, which underlies the autotrophic nutrition of plants.

Videos Images Podcasts. Additional Info. Load Previous Page. Asexual reproduction. Learn about the various forms of asexual plant reproduction; bulb, sscience, plantlet, and cutting. Plants can reproduce asexually in a variety what is chapter 13 bankruptcy rules ways. Learn about bulb, gemma, plantlet, and cutting forms of asexual plant reproduction. Analyze how light affects plants' uptake of carbon dioxide and emission of oxygen.

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Reproduction, the genome and gene expression

Sep 17,  · The key difference between sexual and asexual reproduction is that sexual reproduction involves two parents of the opposite sex while asexual reproduction involves a single parent.. The ability to reproduce and produce a new generation of the same species is one of the fundamental characteristics of a living organism. It involves the transmission of the genetic material . Asexual reproduction in starfish takes place by fission or through autotomy of arms. In fission, the central disc breaks into two pieces and each portion then regenerates the missing parts. In autotomy, an arm is shed with part of the central disc attached, which continues to live independently as a "comet", eventually growing a new set of arms. May 11,  · Asexual reproduction in the plants. The asexual reproduction is the production of new plants without using of seeds, it can incorporate new characteristics into the plants, it is easier and cheaper, it can produce uniform plants, and some plants do not produce the seeds.

The key difference between sexual and asexual reproduction is that sexual reproduction involves two parents of the opposite sex while asexual reproduction involves a single parent.

The ability to reproduce and produce a new generation of the same species is one of the fundamental characteristics of a living organism.

It involves the transmission of the genetic material from the parental generation to the offspring generation, ensuring the characteristics of the species and perpetuating the characteristics of parental organisms.

Before a new individual reaches its own reproductive stage, it normally has to go through a period of growth and development. Some members of the species will die before they reach reproductive age due to predation, disease and accidental death. So the remaining species will only able to produce more offspring and contribute to the continuation of the species. There are two basic types of reproduction; namely, asexual and sexual reproduction.

Overview and Key Difference 2. What is Sexual Reproduction 3. What is Asexual Reproduction 4. Similarities Between Sexual and Asexual Reproduction 5. Sexual reproduction is a type of reproduction that involves two types of parents and the combining of genetic material of each parent.

Parents produce gametes , and gametes fuse with each other during the sexual reproduction. As a result of syngamy , a diploid cell called zygote forms at the end of the sexual reproduction. Based on the types of gametes fusing with each other, there are two types of sexual reproduction; namely, isogamy and heterogamy. Isogamy is the union of structurally similar physiologically different gametes. It is found only in lower forms such as Protozoa.

Heterogamy is the fusion of two clearly different kinds of gametes, distinguished as ovum and sperm. Fertilization is the main event of sexual reproduction. However, there are some events occur before and after fertilization. Pre-fertilization events include gametogenesis and gamete transfer while post-fertilization events include the formation of zygote and embryo.

When compare sexual and asexual reproduction, sexual reproduction creates genetic diversity among the offspring. Genetic diversity is important since it provides material for natural selection. Also, genetic diversity is a key to evolution. As a result of recombination of DNA during the gamete formation by meiosis , genetically different gametes are produced. These gametes create the genetic diversity among the offspring.

Asexual reproduction is one of the two main modes of reproduction. It involves only one parent. Hence, the offsprings are genetically identical with the parent. Prokaryotes such as bacteria and unicellular eukaryotic organisms such as Amoeba and Paramoecium reproduce asexually by cell division or binary fission of the parent cell.

Hence, asexual reproduction is a type of reproduction done by a single organism without production of gametes. It usually results in the production of identical offspring, the only genetic variation arising as a result of random mutation among the individuals.

There are three common modes of asexual reproduction: fission, budding and fragmentation in animals. Lower animal phyla such as prokaryotes, eukaryotes, cnidarians and Platyhelminthes use this type of reproduction. Sexual and asexual reproduction are two main types of reproduction shown by living organisms. The key difference between sexual and asexual reproduction is that sexual reproduction occurs between two parents while asexual reproduction occurs via a single parent.

Asexual reproduction requires only a single divisible cell to produce a new organism, whereas sexual reproduction requires two gametes, their formation and fusion. Hence, this is also a difference between sexual and asexual reproduction. Moreover, a further difference between sexual and asexual reproduction is that sexual reproduction requires the formation of sexual organs, but asexual reproduction generally occurs without them.

Besides, gamete production takes place through meiosis in sexual reproduction. During the meiosis, genetic recombination is a common process.

Hence, gametes show genetic variation, and it leads to the genetic diversity between offspring in sexual reproduction. However, asexual reproduction does not involve meiosis or genetic recombination. Therefore genetic variation is very low in asexual reproduction. Therefore, this is also a significant difference between sexual and asexual reproduction.

Sexual reproduction is a method of reproduction in which combination of genetic material of two individuals takes place in order to produce offspring. On the other hand, asexual reproduction is the second mode of reproduction in which no genetic recombination occurs, or no fertilization occurs. Hence, two parents involve in sexual reproduction while only single parent involves in asexual reproduction. Sexual reproduction results in genetically different offspring while asexual reproduction produces genetically identical offspring.

Thus, this summarizes the difference between sexual and asexual reproduction. Nature News, Nature Publishing Group. Available here 2. Available here. Samanthi Udayangani holds a B. Degree in Plant Science, M. Figure Sexual Reproduction. Figure Binary Fission.

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