A. To understand the nature of an experimental subject
I think DeniceSandidge. DNA is made up of molecules known as nucleotide, which are the building block s of nucleic acid. Each nucleotide compose of pentose sugar, phosphate group and four nitrogenous base. The four types of nitrogenous bases found in nucleotide are adenine, guanine, thymine and cytosine hope this helps pls thank me
This produces several negative effects on the biodiversity of the river ecosystem.
<u>Explanation:</u>
The Susquehanna river is polluted by the excess release of nutrients like phosphorous and nitrogen from agricultural land and sewage treatment plants. This can adversely affect the health of the river. The excess of nutrients will accelerate the growth of algae in the river.
The dead algae that settle at the bottom of the river decay by consuming the oxygen present in the river. This will reduce the amount of dissolved oxygen in the river and affect aquatic life.
Thick algal growth partially prevents the penetration of sunlight into the water and this affects the growth of submerged plants which are food to the fish.
The genetic code is based upon reading 3 bases at a time
there are 4 nucleotides bases in DNA and 20 amino acids .
In order to incorporate all the amino acids we consider 3 bases in genetic code
4 x 4 x 4 = 64
if we would take 2 bases -
4x4 = 16 that would leave out 4 amino acids without a code .
B I think(sorry if you get this wrong)