File:Human idiogram-chromosome 21.jpg: Difference between revisions
From Embryology
Line 9: | Line 9: | ||
* about 1.5 % of the total DNA in cells | * about 1.5 % of the total DNA in cells | ||
* contains between 300 and 400 genes (of human estimated 20,000 to 25,000 total genes) | * contains between 300 and 400 genes (of human estimated 20,000 to 25,000 total genes) | ||
* | * [[trisomy 21]] or Downs Syndrome - additional copy of this chromosome | ||
* partial monosomy 21 - missing segment of the chromosome in each cell | |||
* ring chromosome 21 - circular structure, occurs when there are two breaks in a chromosome and the ends of the chromosome then fuse together | |||
Revision as of 10:54, 9 May 2011
Human Idiogram - Chromosome 21
Idiogram (karyogram) - A drawing or photograph of the chromosomes of a particular cell.
Chromosome 21
- the smallest human chromosome
- about 47 million base pair
- about 1.5 % of the total DNA in cells
- contains between 300 and 400 genes (of human estimated 20,000 to 25,000 total genes)
- trisomy 21 or Downs Syndrome - additional copy of this chromosome
- partial monosomy 21 - missing segment of the chromosome in each cell
- ring chromosome 21 - circular structure, occurs when there are two breaks in a chromosome and the ends of the chromosome then fuse together
| |
Idiogram Chromosome Banding - The term refers to the light and dark pattern, seen after staining with a dye, of individual chromosomes identified in metaphase. It is only in meiosis and mitosis during metaphase that chromosomes can be easily identified, during the normal cell life (interphase) the chromosomes are unravelled and distributed within the nucleus in chromosome territories. A band is that part of a chromosome which is clearly distinguishable from nearby regions by appearing darker or brighter with one or more banding techniques. | |
Genetic abnormality locations: 1-4 | 5-8 | 9-12 | 13-16 | 17-20 | 21-XY | sSMC | |
| |
Links: Genetics | Abnormal Development - Genetic |
Cite this page: Hill, M.A. (2024, April 27) Embryology Human idiogram-chromosome 21.jpg. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/File:Human_idiogram-chromosome_21.jpg
- © Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 13:51, 23 April 2011 | 31 × 142 (2 KB) | S8600021 (talk | contribs) | ==Human Idiogram - Chromosome 21== Idiogram- A drawing or photograph of the chromosomes of a particular cell. This drawing does not include the mitochondrial DNA. {{Human chromosomes}} Category:Genetics Category:Chromosome [[Category:Molecula |
You cannot overwrite this file.
File usage
The following 3 pages use this file: