Diploid organisms

D. melanogaster is a diploid organism with four pairs of chromosomes sex chromosomes (XX or XY), and three pairs of autosomes consisting of a punctiform chromosome 4 and chromosomes 2 and 3 which each bear about 40 percent of the genes - versus 20 percent on chromosome X. 

SOMATIC CELL One of the two cell types (the other being a germ cell) of a multicellular diploid organism it contains a diploid number of chromosomes and is involved in all functions of the organism except fertilization. 

TRISOMIC Pertaining to the presence of one extra chromosome in an otherwise diploid organism. 

The expression of the mutant genotype depends in turn on certain factors such as the turnover rate of the product proteins, the rapidity of cell division and, in diploid organisms, the dominance or recessivity of the mutation. 

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

Meiotic recombination in diploid organisms requires extensive sequence homology between the recombining partners and is called homologous recombination. This term also describes certain recombinational events between bacterial chromosomes. Most bacterial homologous recombination processes share a common requirement for the RecA protein or its counterpart. 

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... 

Because Neurospora is a eukaryotic organism, the genetic damage measured with a two-component heterokaryon should be of the same type that occurs in higher diploid organisms. In fact, we believe that this system... 

Unfortunately, desirability by itself does not get results. For diploid organisms it is not always possible to identify the haplotype of a single allele. Consider the simplest case, determining the haplotype of alleles when there are... 

Heterozygous In a diploid organism, the possession of two different alleles for a given gene (as opposed to two copies of the same allele). Compare homozygous. 

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