Chromosomes, Alleles, Genes WHAT???

Question

Okay so do in One single, unduplicated chromosome, How many genes are there? How many alleles? Is there a standard to how many are in one chromosome?

Answer 1

The number of genes in any organism is directly related to the number of functions required to construct that organism and determine its physiological characteristics. It is generally assumed that with increasing complexity the number of genes must increase.
But, how many genes in a chromosome? This is very variable, and (more-or-less) depends on the length of the chromosome. Some chromosomes are very long and some are very short. In some organisms there are hundreds of chromosomes and in others there are only a few. At opposite ends of the scale are Aulacantha (a protozoan) with 1600 chromosomes and Myrmecia pilosula (an ant) with 2. (These are the diploid number 2n so this would be 800 pairs and 1 pair respectively)
In humans, for example, there are 23 pairs of chromosomes. Twenty two pairs of autosomal and 1 pair of sex chromosomes (X & Y). Chromosome 21 (as stained and seen down a light microscope) is about 10 times shorter than chromosome 1.
Also, genes may be split across two or several chromosomes. So, there is no simple answer to your first question. And the same goes for your second question. An allele is an alternative form of a gene. Some genes may have two or three alleles and some may have many, it depends on the gene and the organism. Think of the gene for eye color in humans; one can have brown, blue, green, hazel and black eyes. These are alternative forms, alleles, of the gene for eye color.

Answer 2

There are no fixed number of genes attached to each chromosome. They vary anywhere between nearly 3000 and a little over 200. Check out wikipedia or something for a chart.

Now, alleles are traits expressed by genes. It's more difficult to tie the number of traits expressed by which genes in which chromosome as we aren't done mapping the human genome yet. Think of it this way - there is no single object called an allele. I can't pick up an allele and hold it in my hand any more than I can pick up color and hold it in my hand. It's an abstract. However, the traits these alleles express are physical, such as eye color, hair color, number of fingers, proclivity to cancer, etc.

Answer 3

Different chromosomes are different sizes. The bigger chromosomes have a lot more genes than the smaller chromosomes have.

Go to the site listed below and click up the number of each chromosome to see an estimate of the number of genes on that chromosome.