What is the difference between X and Y chromosomes?
Gender is determined by sex chromosomes. XX is associated with female chromosomes and XY are termed as male chromosomes.
The main difference between X and Y chromosomes is that X chromosome is a sex chromosome that determines female gender whereas Y chromosome is a sex chromosome that determines male gender.
Comparison Table (XX vs XY Chromosomes)
|Basic Terms||X Chromosome||Y Chromosome|
|Meaning||It is a sex chromosome that occurs in paired among female cells and singles among male cells||It is a sex chromosome which is present in male cells|
|Sex Determination||Contain genes that determine female gender||Contain genes that determine male gender|
|Size and Number||Tend to be bigger and about 155 million base pairs||Tend to be smaller and about 59 million base pair|
|Represent||5 percent of the human genome||2 percent of the human genome|
|Number of Genes||About 100 genes||About 70 genes|
|Female and Male genotype||XX genotype||XY genotype|
|SYR Gene||Do not contain SYR gene||Contain SYR gene for testes development|
Read More: Difference between Chromatid and Chromosome
What Is X Chromosome?
It is among the two sex chromosomes present in human beings. X chromosomes occur in pair among female cells and single among male cells.
X chromosomes are numerous and they tend to represent 5 percent of the human genome. During embryo development, one X chromosome tends to be inactivated permanently.
What Is Y Chromosome?
It is a sex chromosome present in male cells. They are key determinants of male gender among human beings.
The chromosomes are less in number and they tend to represent about 2 percent of the human genome. Besides that, they contain fewer genes than X chromosomes.
Main Difference between X and Y Chromosomes
- X chromosome contain more genes whereas Y chromosome contain fewer genes
- X chromosomes have 155 base pairs whereas Y chromosomes have 59 base pairs
- X chromosome represent about 5 percent of the human genome whereas the Y chromosome represents about 2 percent of the human genome
- X chromosome contain female sex determination whereas Y chromosome contain male sex determination
- Y chromosome contain SYR gene for testes development whereas X chromosome does not contain SYR gene.
Read More: Difference between Gene and Allele
Similarities between X and Y Chromosome
- Both are sex chromosomes in human beings
- Both contain p arm, q arm and a centromere.
- Both consists of pseudoautosomal regions at both termini
- Both contain homologous chromosomes
The core difference between X and Y chromosome is that X chromosome is used in determining female sex and Y chromosome in determining male gender.
Female cells have two X chromosomes and male cells have one X chromosome and one Y chromosome. Hence, these chromosomes are regarded as sex chromosomes.
More Sources and References
- Sex Chromosome. NCBI
- Sex of Offspring. Nature