Haploid organism

Diploid organisms carry two copies (alleles) of each gene, whereas haploid organisms carry only one copy. 

A diploid organism is one where the somatic cells contain two copies of the genome. Most plants and animals are diploid. Haploid organisms contain only one copy of their genome. Most fungi, algae, and bacteria are haploid. 

Neurospora is a haploid organism, but with the use of a two-component heterokaryon, it can be used to study many of the same genetic effects that occur in diploid organisms (Atwood, 1949 Atwood and Mukai, 1953, 1954). Forced heterokaryons between two different haploid strains with different biochemical requirements produce three types of conidia two different homokaryotic types that will grow only on supplemented media, and a heterokaryotic type that will grow on minimal medium. The... 

The 3x10 base pairs of DNA in humans are organized into the haploid complement of 23 chromosomes. The exact sequence of these 3 billion nucleotides defines the uniqueness of each individual. 

The amount of genomic DNA in a particular organism is roughly proportional to the complexity of the organism. Table shows the content of DNA in the genomes of several widely different organisms. The data are normalized to a haploid set of chro-mosomes, since some cells listed are haploid and others are diploid. The DNA content... 

Organism see footnotes for sequence information Millions of nucleotide base pairs (Mb) Number of chromosomes (haploid) Estimated number of genes... 

It is presumably the ability to survive as a heterozygote, even with one or more highly deleterious mutations, that has led to the dominance of the diploid phase in higher plants and animals.76 However, to the biochemical geneticist organisms with a haploid phase offer experimental advantages because recessive mutants can be detected readily. 

ABCW RELATIONSHIP The relationship noted by Abrahamson, Bender, Conger, and Wolff wherein the per-gene rate of radiation-induced mutation is directly proportional to the haploid amount of an organism s DNA. 

ANEUPLOID An organism or cell whose somatic nuclei do not contain an exact multiple of the haploid number of chromosomes, one or more chromosomes being represented more (or fewer) times than the rest. (See also MONO-SOMIC and TRISOMIC)... 

DIPLOID An organism or cell having two complete sets of chromosomes, with each set typically of a different parental origin the chromosome number twice that typically present in gametes. (See also HAPLOID and POLYPLOID)... 

DISOMIC Having two of a given chromosome in an otherwise haploid cell or organism. 

GAMETE A mature germ cell (i.e., a sperm or an egg) possessing a haploid chromosome set and capable of initiating formation of a new organism by fusion with smother gamete. 

PLOIDY Refers to the number of sets of chromosomes in a cell or organism—1 set in monoploids (haploids), 2 in diploids, 3 in triploids, 4 in tetraploids, etc. 

ZYGOTE A diploid cell formed by the fusion of two haploid gametes from eukaryotic organisms with sexual reproduction. 

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