Genetics Lab Write-Up

Genes are inherited to determine how an organism will look, develop, and function. A genetic cross occurs when two individuals produce an offspring that carries part of the genetic makeup of each parent. Genes that are passed on from parent to child determine the traits that are the basis for evolution. Evolution takes place when traits become less common or more frequent in a population. Genes are quite significant in inheritance because they determine the transmission of conditions or diseases from generation to generation.

These two labs outlined genetic inheritance through the illustration of the effects of dominant and recessive genes. A phenotype is the actual physical appearance of an adult/organism. It is the resultant of the dominant genes in ones genetic makeup. (This can be influenced by the environment as well. For instance, the development of a suntan may result in the change of ones phenotype--the appearance of their skin coloring).

A genotype is not visible through physical appearance, but is an internal component, rather. The genotype is comprised of two alleles.

Alleles are represented in a Punnett Square and can be either dominant or recessive.
Dominant refers to the gene that is represented in the phenotype--that is, the trait that is evident in physical appearance. If a phenotype has two types of alleles the allele that is not physically apparent is known as recessive.



























In the above Punnett Square scenario a genetic cross was made between two heterozygous long winged adult flies. The genotype of both adult flies is Ll. The phenotype is long winged. The alleles for the parents are L and l. L is the dominant gene, and is evident by the long winged appearance of the flies, while l is recessive.



The following image shows the genetic makeup of two dragons. There are several phenotypes and genotypes shown for the pair. The blue coloring and presence of horns both illustrate a phenotype. The genotype for horns in the scenario is Hh. H is dominant, while h is recessive. Had the alleles both been h no horns would be present.



















I found the following website to be of interest;



http://www.uvm.edu/~cgep/Education/Inheritance2.html

(The site outlines inheritance patterns regarding conditions and diseases passed from parents to offspring).

Understanding genetic inheritance is vital to understanding evolution. As such, genetic manipulation in today’s society is viewed as manipulating evolution. Good, bad, or indifferent regarding the issue, these labs left me with that to consider. With the click of a mouse I could change the characteristics of a dragon and be instantly gratified in the resulting phenotype. The origins of the basis of genetic manipulation and the significance of genes in evolution are much more clear to me after having completed these activities.