PloidyPloidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomalgenes. Here sets of chromosomes refers to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair—the form in which chromosomes naturally exist.
MeiosisCell division producing haploid gametesIn meiosis, the chromosomes duplicate (during interphase) and homologous chromosomes exchange genetic information (chromosomal crossover) during the first division, called meiosis I. The daughter cells divide again in meiosis II, splitting up sister chromatids to form haploid gametes.
ChromosomeDNA molecule containing genetic material of a cellDifferent representations of chromosomesMain parts of a condensed chromosomeCondensed chromosome (purple rod) inside a bone marrow erythrokaryocyte undergoing mitosisDiagram of a duplicated and condensed metaphase eukaryotic chromosome: ChromatidCentromereShort armLong armA chromosome is a package of DNA containing part or all of the genetic material of an organism.
Homologous chromosomeHomologous chromosomes or homologs are a set of one maternal and one paternal chromosome that pair up with each other inside a cell during meiosis. Homologs have the same genes in the same loci but possibly different alleles, where they provide points along each chromosome that enable a pair of chromosomes to align correctly with each other before separating during meiosis.
EukaryoteDomain of life whose cells have nucleiThe eukaryotes () are cellularorganisms of the domainEukaryota or Eukarya, which have a distinct cell nucleus (formed by a nuclear membrane), membrane-bound organelles and organization supported by a cytoskeleton. Extant eukaryotes are traditionally grouped into four kingdoms: animals, plants, fungi and protists.
Cell nucleusThe cell nucleus (from Latin or 'kernel, seed'; pl.: nuclei) is a membrane-bound organelle found in eukaryotic cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have no nuclei, and a few others including osteoclasts have many.
Somatic cellIn cellular biology, a somatic cell (from Ancient Greekσῶμα (sôma)'body'), or vegetal cell, is any biological cell forming the body of a multicellular organism other than a gamete, germ cell, gametocyte or undifferentiated stem cell. Somatic cells compose the body of an organism and divide through mitosis. In contrast, gametes derive from meiosis within the germ cells of the germline and they fuse during sexual reproduction.
OrganismAn organism is any living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Several criteria, few of which are widely accepted, have been proposed to define what constitutes an organism. Among the most common is that an organism has autonomous reproduction, growth, and metabolism. This would exclude viruses, even though they evolve like organisms.
GameteA gamete ( GAM-eet ), reproductive cell, or sex cell, is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. The name gamete was introduced by the German cytologist Eduard Strasburger in 1878. The type of gamete an organism produces determines its sex and sets the basis for the sexual roles and sexual selection. Female gametes are called ova or egg cells, and male gametes are called sperm.
Cell (biology)The cell is the basic structural and functional unit of all forms of life or organisms. The term comes from the Latin word cellula meaning 'small room'. A biological cell basically consists of a semipermeablecell membrane enclosing cytoplasm that contains genetic material. Most cells are only visible under a microscope. Except for highly-differentiated cell types (examples include red blood cells and gametes) most cells are capable of replication, and protein synthesis.
mesopolyploidRelated word or term.neopolyploidRelated word or term.*As an Amazon Associate I earn from qualifying purchases.