what are chromosomes? where are they located? *somatic cells *nucleus how many are there? diploid...
TRANSCRIPT
What are chromosomes?
Where are they located? *Somatic Cells *Nucleus
How many are there? Diploid (2n) Different species have a different # of chromosomes
How are chromosomes arranged? *karotype
Types of chromosomes *autosomes *sex chromosomes
Common Name Genus and Species Diploid ChromosomeNumber
Buffalo Bison bison 60
Cat Felis catus 38
Cattle Bos taurus, B. indicus 60
Dog Canis familiaris 78
Donkey E. asinus 62
Goat Capra hircus 60
Horse Equus caballus 64
Human Homo sapiens 46
Pig Sus scrofa 38
Sheep Ovis aries 54
Chromosome classification
Centromere position and length of arms can assist in identifying specific pairs of chromosomes, but inevitably several or many pairs of chromosomes appear identical by these criteria.
Q banding: chromosomes are stained with a fluorescent dye such as quinacrine G banding: produced by staining with Giemsa after digesting the chromosomes with trypsin C banding: chromosomes are treated with acid and base, then stained with Giesma stain
Each of these techniques produces a pattern of dark and light bands along the length of the chromosomes.
Importantly, each chromosome displays a unique banding pattern, analagous to a "bar code.”
Parts of a gene *Promotor
*Exons
*Introns *Protein “codes”
*Stop Codes
Every cell within an organism has the same genetic composition (with the exception of its gametes), and yet, obviously skin tissue is very different from nervous tissue.Both neuron and epithelial cell have the genes encoding for neural- and epithelial-specific proteins, but each cell only expresses the genes that it requires, and not other tissue-specific genes.