|
Genome Sizes
The size of genomes vary, as noted in the previous page on chromosomes.
For example, the human genome is estimated to contain over 3 billion base pairs, while the E. coli genome contains 4.6 million base pairs.
The Database of Genome Sizes (DOGS) lists the genome sizes (in base pairs) of various organisms.
Karyotypes
A karyotype is an image of a cell showing all the chromosomes
within that cell, usually during metaphase of mitosis.
Karyotypes can be used to check for chromosomal abnormalities, such as
trisomy (three copies of a chromosome rather than two), or chromosomes that
are missing pieces or contain extra stretches of DNA.
The Cytogenetics Gallery by the Department of Pathology, University of Washington, Seattle, WA, provides a nice overview of chromosomes and karyotypes.
|
