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Information about Gametes

A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilisation (conception) in organisms that reproduce sexually. In species which produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual which produces the larger type of gamete—called an ovum (or egg)—and a male produces the smaller type—called a spermatozoon (or sperm cell). This is an example of anisogamy or heterogamy, the condition wherein females and males produce gametes of different sizes. In contrast, isogamy is the state of gametes from both sexes being the same size. The name gamete was introduced by the Austrian biologist Gregor Mendel.

Creation

Main article: gametogenesis
The creation of gametes is gametogenesis, and during it gametocytes divide by meiosis into gametes. Meiosis is a process of cellular division that reduces the number of sets of chromosomes from two to one (i.e., produces haploid gametes). Organs that produce gametes are called gonads in animals, and archegonia or antheridia in plants.

Gamete cycle

A gamete of one generation ultimately creates a gametes in the next generation, but still keeping the same quantity of genetic information.

Gametes are haploid cells; that is, they contain one complete set of chromosomes (the actual number varies from species to species). When two gametes fuse (in animals typically involving a sperm and an egg), they form a zygote—a cell that has two complete sets of chromosomes and therefore is diploid. The zygote receives one set of chromosomes from each of the two gametes through the fusion of the two gamete nuclei. After multiple cell divisions and cellular differentiation, a zygote develops, first into an embryo, and ultimately into a mature individual capable of producing gametes.

Dissimilarity

In contrast to a gamete, the diploid somatic cells of an individual contain one copy of the chromosome set from the sperm and one copy of the chromosome set from the egg; that is, the cells of the offspring have genes expressing characteristics of both the father and the mother. A gamete's chromosomes are not exact duplicates of either of the sets of chromosomes carried in the somatic cells of the individual that produced the gametes. They can be hybrids produced through crossover(a form of genetic recombination) of chromosomes, which takes place in meiosis. This hybridization has a random element, and the chromosomes tend to be a little different in every gamete that an individual produces. This recombination and the fact that the two chromosome sets ultimately come from either a grandmother or a grandfather on each parental side account for the genetic dissimilarity of sibling's.

Examples

For example, mammal gametes are called eggs and sperms.
Ancient Greek refers to the second stage in the history of the Greek language[1] as it existed during the Archaic (9th–6th centuries BC) and Classical (5th–4th centuries BC) periods in Greece.
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Fertilization (also known as conception, fecundation and syngamy), is fusion of gametes to form a new organism of the same species. In animals, the process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo.
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Plantae
  • Chromalveolata
  • Heterokontophyta
  • Haptophyta
  • Cryptophyta
  • Alveolata

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    • Sexual reproduction is a union that results in increasing genetic diversity of the offspring. It is characterized by two processes: meiosis, involving the halving of the number of chromosomes; and fertilisation, involving the fusion of two gametes and the restoration of the
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    Female (♀) is the sex of an organism, or a part of an organism, which produces ova (egg cells). The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon is produced by the male.
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    ovum (plural ova) is a haploid female reproductive cell or gamete. The word is derived from Latin, meaning egg or egg cell. Both animals and embryophytes have ova. The term ovule
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    Male (♂) refers to the sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilisation.
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    A spermatozoon or spermatozoan (pl. spermatozoa), from the ancient Greek σπέρμα (seed) and ζῷον (living being) and more commonly known as a sperm cell
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    Anisogamy (also called heterogamy) refers to a form of sexual reproduction involving gametes of different sizes. The smaller gamete is considered to be male (sperm cell) whereas the larger gamete is regarded as female (egg cell).

    There are several types of anisogamy.
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    Heterogamy has a number of biological definitions:
    • In reproductive biology, heterogamy is the alternation of differently organized generations, applied to the alternation between parthenogenetic and a sexual generation.

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    Isogamy refers to a form of sexual reproduction involving gametes of the same size. Since both gametes look alike, they cannot be classified as "male" or "female." Instead, organisms undergoing isogamy are said to have different mating types, most commonly noted as "+" and "-"
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    Anthem
    Land der Berge, Land am Strome   (German)
    Land of Mountains, Land on the River
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    Gametogenesis is a process by which the diploid germ cells undergo a number of chromosomal and morphological changes to form mature haploid gametes. Depending on the biological life cycle of the organism, gametogenesis occurs by meiotic division of gametocytes into various gametes
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    gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametes during gametogenesis. Male gametocytes are called spermatocytes, and female gametocytes are called oocytes.
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    meiosis (IPA: /maɪˈəʊsɪs/) is the process by which one diploid eukaryotic cell divides to generate four haploid cells often called gametes.
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    The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, sperm and egg cells are gametes.
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    Figure 1: A representation of a condensed eukaryotic chromosome, as seen during cell division.]] A chromosome is a single large macromolecule of DNA, and constitutes a physically organized form of DNA in a cell.
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    For other meanings see Zygote (disambiguation).
    A zygote (Greek: ζυγωτόν) is a cell that is the result of fertilization.
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    nucleus (3) ribosome (4) vesicle (5) rough endoplasmic reticulum (ER) (6) Golgi apparatus (7) Cytoskeleton (8) smooth ER (9) mitochondria (10) vacuole (11) cytoplasm (12) lysosome (13) centrioles]]

    In cell biology, the nucleus (pl.
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    Cell division is a process by which a cell, called the parent cell, divides into two cells, called daughter cells. Cell division is usually a small segment of a larger cell cycle. In meiosis however, a cell is permanently transformed and cannot divide again.
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    Cellular differentiation is a concept from developmental biology describing the process by which cells acquire a "type". The morphology of a cell may change dramatically during differentiation, but the genetic material remains the same, with few exceptions.
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    Developmental Biology is the official journal of the Society for Developmental Biology. It publishes research on the mechanisms of development, differentiation, and growth in animals and plants at the molecular, cellular, and genetic levels.
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    A somatic cell is generally taken to mean any cell forming the body of an organism: the word "somatic" is derived from the Greek word sōma (σώμα), meaning "body". Somatic cells, by definition, are not germline cells.
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    Genetic recombination is the process by which a strand of DNA is broken and then joined to the end of a different DNA molecule. In eukaryotes recombination commonly occurs during meiosis as chromosomal crossover between paired chromosomes.
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    Genetics is the science of heredity and variation in living organisms.[1][2] Knowledge of the inheritance of characteristics has been implicitly used since prehistoric times for improving crop plants and animals through selective breeding.
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    Family is a Western term used to have denote a domestic group of people, or a number of domestic groups linked through descent (demonstrated or stipulated)
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