biology help?

Question

what is the disease alkaptonuria and how garrod was the first to discover the connection between genes, enzymes, and metabloism

Answer 1

This web site can tell you what alkaptonuria is: http://en.wikipedia.org/wiki/Alkaptonuria

Also look here for some information on Garrod:
http://en.wikipedia.org/wiki/Archibald_Garrod

To re-phrase your question, Garrod made a very important connection between an observable metabolic defect that caused this disease (black urine), the mutated enzyme that was responsible for this metabolic defect (unable to properly process a chemical in urine), and the fact that this defect was inherited in an autosomal recessive fashion (meaning that the affected person must inherit two mutated genes). Search for Archibald Garrod or "one gene, one enzyme hypothesis" for more information.

One question to keep in mind is, why does it matter that the disease is inherited in a recessive fashion? We have two copies of all our autosomal genes (chromosomes 1-22) so if a disease is inherited in a recessive pattern that must mean that both copies of that particular gene are mutated. That must mean that the disease is not observed when there is only one mutation because the one good copy is able to compensate for the bad one. In the case of a gene coding for an enzyme this is easy because enzymes are catalysts and can work at a very fast rate.

Answer 2

Try either this site:

http://www.emedicine.com/ped/topic64.htm

or this one:

http://en.wikipedia.org/wiki/Alkaptonuria