A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilization (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 tadpole-like type—called a sperm. This is an example of anisogamy or heterogamy, the condition wherein females and males produce gametes of different sizes (this is the case in humans, the human ovum is approximately 20 times larger than the human sperm cell). 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. Gametes carry half the genetic information of an individual, one chromosome of each type. In humans an ovum can only carry X chromosome (of the X and Y chromosomes) where as a sperm can carry either an X or a Y, hence, it has been suggested that males have the control of the gender of any resulting zygote as the genotype of the sex-determining chromosomes of a male must be XY and a female XX. Beginning of Homers Odyssey The Ancient Greek language is the historical stage of the Greek language[1] as it existed during the Archaic (9th–6th centuries BC) and Classical (5th–4th centuries BC) periods in Ancient Greece. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... Categories: Biology stubs ... Domains and Kingdoms Nanobes Acytota Cytota Bacteria Neomura Archaea Eukaryota Bikonta Apusozoa Rhizaria Excavata Archaeplastida Rhodophyta Glaucophyta Plantae Heterokontophyta Haptophyta Cryptophyta Alveolata Unikonta Amoebozoa Opisthokonta Choanozoa Fungi Animalia An ericoid mycorrhizal fungus Life on Earth redirects here. ... Sexual reproduction is a union that results in increasing genetic diversity of the offspring. ... For other uses, see Female (disambiguation). ... A human ovum Sperm cells attempting to fertilize an ovum An ovum (plural ova) is a haploid female reproductive cell or gamete. ... This article is about the Male sex. ... For other uses, see Sperm (disambiguation). ... Gametes (in Greek: γαμέτες) —also known as sex cells, or spores—are the specialized germ cells that come together during fertilization (conception) in organisms that reproduce sexually. ... Kaguya is one success from 460 attempts at growing embryos. ... A gamete is a specialized germ cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. ... “Mendel” redirects here. ... A DNA sequence (sometimes genetic sequence) is a succession of letters representing the primary structure of a real or hypothetical DNA molecule or strand, The possible letters are A, C, G, and T, representing the four nucleotide subunits of a DNA strand (adenine, cytosine, guanine, thymine), and typically these are... For information about chromosomes in genetic algorithms, see chromosome (genetic algorithm). ... Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. ... ‹ The template below (Expand) is being considered for deletion. ... ... Gender in common usage refers to the sexual distinction between male and female. ... For other meanings see Zygote (disambiguation). ... This article does not cite any references or sources. ...

Gametogenesis

Main article: Gametogenesis

Scheme showing analogies in the process of maturation of the ovum and the development of the spermatids.

The production of gametes is termed gametogenesis, during which phase gametocytes divide by meiosis into gametes. Meiosis reduces the number of sets of chromosomes from two to one (i.e., produces haploid gametes from diploid gametocytes). Organs that produce gametes are called gonads in animals, and archegonia or antheridia in plants. Gametogenesis is the creation of gametes by meiotic division of gametocytes into various gametes. ... Image File history File links Gray7. ... Image File history File links Gray7. ... A gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametes. ... For the figure of speech, see meiosis (figure of speech). ... The gonad is the organ that makes gametes. ... An archegonium (pl: archegonia) (from the Greek arche = beginning and gonos = born) is a multicellular structure or organ of the gametophyte phase of certain plants producing and containing the ovum or female gamete. ... Diagram of antheridium anatomy An antheridium (plural: antheridia) is a structure or organ of the gametophyte phase of certain plants producing and containing the spermatids or male gametes. ...

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 half a 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. Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ... For information about chromosomes in genetic algorithms, see chromosome (genetic algorithm). ... For other meanings see Zygote (disambiguation). ... Diploid (meaning double in Greek) cells have two copies (homologs) of each chromosome (both sex- and non-sex determining chromosomes), usually one from the mother and one from the father. ... HeLa cells stained for DNA with the Blue Hoechst dye. ... This does not adequately cite its references or sources. ... In the center of the diagram are three of the early steps in the development of a mammal. ... Views of a Foetus in the Womb, Leonardo da Vinci, ca. ... For other uses, see Embryo (disambiguation). ...

Dissimilarity

In contrast to a chromosome, the diploid somatic cells of an many 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 siblings. This article does not cite any references or sources. ... Thomas Hunt Morgans illustration of crossing over (1916) Homologous Recombination is the process by which two chromosomes, paired up during prophase I of meiosis, exchange some distal portion of their DNA. Crossover occurs when two chromosomes, normally two homologous instances of the same chromosome, break and then reconnect but... Genetic recombination is the process by which a strand of the genetic material (usually DNA; but can also be RNA) is broken and then joined to the end of a different DNA molecule. ... This article is about the general scientific term. ... For other uses, see Family (disambiguation). ...