Associate Program Material

DNA Worksheet

Answer the following in at least 100 words:

Describe the structure of DNA.
"DNA is a polymer consisting of continuing subunits termed nucleotides." (Simon, Reece, & Dickey 2010) DNA is a double-stranded construction that is described as a double helix. A double helix is similar to a spiral staircase in which every step symbolizes the base pairs and the railings, and sides illustrate the bonding between the phosophate and deoxyribose molecules. Essentially DNA is one of the main building blocks of an organisms life. It has a chemical signature made up of four different chemical bases: adenine (A), guanine (G), cytosine (C) and Thymine (T). Furthermore, "human DNA consists of more than 3 billion bases, and more than 99 percent of those bases are the same in all people." (www.ghr.nlm.nih.gov)

How does an organism’s genotype determine its phenotype?
The genotype is the mixture of alleles. Alleles are alternative forms of the same gene that occupy the same location on a chromosome. "At any given locus (the specific site of a particular gene) there are two alleles (one on each chromosome in the pair) a human gets one allele from each parent." (www.sciencelearn.org) In relation to the nature of the genes and the kinds of alleles, a particular trait will be shown (phenotype). "Gene expression can be established by simple dominance, co-dominance, partial dominance or polygenic inheritance. Every instance will show particular traits in various means." (www.sciencelearn.org).

Describe each stage of the flow of information starting with DNA and ending with a trait.

"DNA nucleotide bases consist of a particular code. Specific strands of this code are termed genes." (Simon, Reece, & Dickey 2010) Genes code for particular proteins which ends in specific trait expression. Here is how it occurs, in short,