GENES!

Introduction: Genes, according to our textbook, are a unit of heredity exisiting as alleles on the chromosomes. This section is going to look at the Punnett square and alleles.

Genotype and Phenotype

Genotype is the genes of the individual and Phenotype is the physical characteristics.

Alleles one of two or more alternate forms of a gene that arise by mutation and are found at the same place on a chromosome.

*A quick story. When I was in high school, my biology teach was obsessed with the Human Genome Project. He had a big poster up in his classroom that was only partially complete. Now, it has been completed. It is neat to grow up with something like that.*

To finish up the gene section, here is my lab write up concerning the Punnet Square.

Lab Write Up

Introduction: My mother has blue eyes, straight almost black hair. My father, sister, and brother, all have very very dark, straight hair and brown eyes. I have blue eyes and naturally dirty-blonde curly hair. How did that happen? Either I am adopted (which I wouldn't be surprised) or it had something to do with genetic inheritance. Somewhere along the line, the recessive trait of blue eyes and curly hair became dominant.

Definitions:

Genotype: The actual genes of a person for a particular trait. For example, in the dragon lab, you can see the chromosomes and it highlights the genes found on each.

Phenotype: The physical traits from the genotype. Again, looking at the dragons, you see they have horns, which comes from the dominate trait H.

Allele: Alternative form of the gene. In the “Scenario Five” example you see the Punnett square. In the upper right hand corner you have the genotype of LL. The allele to that would the Ll genotype.

Cross: Breeding to organisms to create an offspring. The Punnett square shows two adult flies and if they were crossed, the square gives an estimate of what their offspring would look like.

Dominant: Referring to alleles; it is the primary trait in the heterozygote, stomping the expression of the recessive trait. For example, the long wings would be the dominate trait in the flies.

Recessive: Again referring to allele; only shows through in a homozygote. In the dragon lab, looking at the traits displayed on the right, you can see that breathing fire is a recessive trait.

What you have just seen are the definitions with some examples pertaining to the pictures above. These are from the online lab. Let's begin with the one with dragons. In this lab, you had to match up the genes to get something that looked completely different to the top dragon to what you see now. To do this, one needs to go through and determine which traits are dominant and which are recessive in the dragon you want it to look like. From there, you change the traits in the bottom one and you end up with twins!

After that, you go into the Punnett square example. This example is to give you an idea as to what potential offspring might look like. You pick two adults. In this case we had two heterozygotes, so I chose the differing alleles (Ll). From there you lay out the traits along the out side of the squares then match them. Three of them will look a like, and the fourth will have a slightly different phenotype.

Conclusions: After going through these labs, it has been determined that I was the kid in the fourth square in the bottom right hand corner. My parents have all of the traits I have, the only problem is they aren't visible on them. This lab gave significant definitions as well as examples from the online simulator.