How many X chromosomes do Drosophila have?
How many X chromosomes do Drosophila have?
In Drosophila, sex determination is achieved by a balance of female determinants on the X chromosome and male determinants on the autosomes. Normally, flies have either one or two X chromosomes and two sets of autosomes.
What is XXY in Drosophila?
Sex Determination in Drosophila The balance between female-determining factors encoded on the X chromosome and male-determining factors encoded on the autosomes determines which sex-specific pattern of transcription will be initiated. Thus, XX, XXY, and XXYY flies are females, while XY and XO flies are males.
Which chromosome is Drosophila?
Female Drosophila have two X chromosomes and males have one X and one Y. The X chromosome (also sometimes referred to as the first chromosome) is slightly larger than a single arm of chromosome 2 or 3 and very nearly acrocentric. The heterochromatic Y chromosome is divided into short (YS) and long (YL) arms.
How many X chromosomes are found in Drosophila melanogaster males?
In Drosophila melanogaster, most cells make this choice independent of their neighbors such that diploid cells with one X chromosome (XY) are male and those with two X chromosomes (XX) are female. X-chromosome number is relayed through regulatory proteins that act together to activate Sex-lethal (Sxl) in XX animals.
Why are Drosophila melanogaster used in genetics?
Drosophila melanogaster, known colloquially as the fruit fly, remains one of the most commonly used model organisms for biomedical science. These tools allow researchers to maintain complex stocks with multiple mutations on single chromosomes over generations, an advance that made flies the premier genetic system [4].
What is strange about the chromosomes of Drosophila compared to most other eukaryotic chromosomes?
Drosophila telomeres use arrays of retrotransposons to maintain chromosome length, while nearly all other eukaryotes rely on telomerase-generated short repeats. Regardless of the DNA sequence, several end-binding proteins are evolutionarily conserved.
Where are Drosophila chromosomes located?
These chromosomes are found in several cell types, the function of which is principally secretory. In Drosophila, the most useful are found in the larval salivary glands.
How many chromosomes are in Drosophila ovum?
By contrast, males are identified as having one X chromosome and one (much smaller) Y chromosome. While drosophila only have a total of 4 chromosomes, they too display sexual dimorphism, with females carrying the double X chromosomes and males carrying XY.
How many chromosomes are present in Drosophila ovum?
While drosophila only have a total of 4 chromosomes, they too display sexual dimorphism, with females carrying the double X chromosomes and males carrying XY. The two X chromosomes in female fruit flies, as in mammals, make them a homozygous sex as compared with the XY condition in males, known as heterozygous.
Do Drosophila have chromosomes?
Polytene Chromosomes in Drosophila The fly, Drosophila melanogaster, is a holometabolous insect with four main stages to its lifecycle: embryo, larva, pupa, adult. As a larva, the organism is primarily concerned with obtaining food for the rapid increase in size characteristic of this stage of development.
What is the life cycle of a Drosophila?
Polytene Chromosomes in Drosophila The fly, Drosophila melanogaster, is a holometabolous insect with four main stages to its lifecycle: embryo, larva, pupa, adult. As a larva, the organism is primarily concerned with obtaining food for the rapid increase in size characteristic of this stage of development.
How do the salivary glands of Drosophila grow?
The salivary glands of Drosophila and some other insects achieve their growth through an increase in cell mass and volume rather than an increase in the number of cells. After an initial population of salivary gland cells is established during early larval development, cell division ceases.
