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SURFACE AREA AND ITS IMPACT ON BIOLOGY

DNA














Home | Works Cited | Mitochondria | Chloroplast | DNA | Fish Respiration | .





HOW IS THE DNA MADE ?

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The extremely long DNA molecule is actually made of a long string of chemical building blocks called “nucleotides.” There are four different nucleotides, which are labeled adenine (A), thymine (T), guanine (G), and cytosine (C). The human genome is made of a sequence of roughly three billion of these nucleotides, and it is about the same size as the genome of a chimpanzee or a mouse. In contrast, a fruit fly has 180 million, a yeast has 12 million, and the flowering weed “thale cress” has 100 million nucleotides of DNA in its genome.

 
 
 
 
 
HOW DOES SURFACE AREA IMPACT DNA? 

In opposition to, fish gills, mitochondria and chloroplast the DNA is a structure that wants to decrease in size. The DNA is the genetic information of an organism (for example a human) and there is an identical DNA in every cell an organism contains. As mentioned before a human DNA is made up of about three billion nucleotides this means that there is a lot of information that must be put in side a nucleus of a cell only 10 - 100 μm big. The DNA in order to fit in side the nucleus is twisted and folded many times to decrease to amount of space it takes up inside the nucleus yet the surface area of the DNA is large enough to contain essential genetic information that not only determine the physical characteristics of an organism but also control the cellular functions.