Search results
Results from the WOW.Com Content Network
Spores can carry either the U chromosome, which results in female gametophytes, or the V chromosome, which results in males. The chromosome number n = 9 is the basic number in many species of Marchantiales. In some species of Marchantiales, plants with various ploidy levels (having 18 or 27 chromosomes) were reported, but this is rare in nature ...
Euploidy and aneuploidy describe having a number of chromosomes that is an exact multiple of the number of chromosomes in a normal gamete; and having any other number, respectively. For example, a person with Turner syndrome may be missing one sex chromosome (X or Y), resulting in a (45,X) karyotype instead of the usual (46,XX) or (46,XY).
Cells of the diploid wheats each contain 2 complements of 7 chromosomes, one from the mother and one from the father (2n=2x=14, where 2n is the number of chromosomes in each somatic cell, and x is the basic chromosome number). The polyploid wheats are tetraploid (4 sets of chromosomes, 2n=4x=28), or hexaploid (6 sets
The basic number of chromosomes in the somatic cells of an individual or a species is called the somatic number and is designated 2n. In the germ-line (the sex cells) the chromosome number is n (humans: n = 23). [4] [5] p28 Thus, in humans 2n = 46. So, in normal diploid organisms, autosomal chromosomes are present in two copies.
Polyploidy is a condition in which the cells of an organism have more than two paired sets of chromosomes. Most species whose cells have nuclei are diploid, meaning they have two complete sets of chromosomes, one from each of two parents; each set contains the same number of chromosomes, and the chromosomes are joined in pairs of homologous ...
Other eukaryotic chromosomes, i.e., mitochondrial and plasmid-like small chromosomes, are much more variable in number, and there may be thousands of copies per cell. The 23 human chromosome territories during prometaphase in fibroblast cells. Asexually reproducing species have one set of chromosomes that are the same in all body cells. However ...
Muntiacus muntjak chromosomes. Muntjac are of great interest in evolutionary studies because of their dramatic chromosome variations and the recent discovery of several new species. The Southern red muntjac (M. muntjak) is the mammal with the lowest recorded chromosome number: The male has a diploid number of 7, the female only 6 chromosomes.
Cytogenetic analysis has shown the haploid chromosome number (n) is variable and varies across species in the genus: [7] A. thaliana is n=5 [8] and the DNA sequencing of this species was completed in 2001. A. lyrata has n=8 but some subspecies or populations are tetraploid. [9]