Answer the following in at least 100 words:
Describe the structure of DNA.
DNA is a nucleic acid, which consist of long chains (polymers) of chemical units (monomers) called nucleotide. A molecule of DNA contains two polynucleotides, each a chain of nucleotides. Each nucleotide consists of a nitrogenous base, a sugar, and a phosphate group. Each DNA strand serves as a mold, or template, to guide reproduction of the other strand. There are four different types of nucleotides found in DNA, differing only in the nitrogenous base. DNA is contained in blood, semen, skin cells, tissue, organs, muscle, brain cells, bone, teeth, hair, saliva, mucus, perspiration, fingernails, urine, feces, etc. The four nucleotides are given one letter abbreviations as shorthand for the four bases: A is for adenine, G is for guanine, C is for cytosine, and T is for thymine.
How does an organism’s genotype determine its phenotype?
An organism’s genotype, its genetic makeup, is the sequence of nucleotide bases in its DNA. The phenotype, the organism’s physical traits, arises from the actions of a wide variety of proteins. The genotype is the descriptor of the genome which is the set of physical DNA molecules inherited from the organism's parents. The phenotype is the descriptor of the phenome, the manifest physical properties of the organism, its physiology, morphology and behavior. For sexually reproducing organisms that physical material consists of the DNA contributed to the fertilized egg by the sperm and egg of its two parents. For asexually reproducing organisms, for example bacteria, the inherited material is a direct copy of the DNA of its parent.
Describe each stage of the flow of information starting with DNA and ending with a trait.
The flow of genetic information, or gene expression, in normal cells is: . This flow of information is dependent on the genetic code, which defines the relation between the sequence of bases in DNA (or its mRNA...
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