Genetics Day 3

Today, we learned of different types of genetics, such as: Incomplete Dominance, Sex-Linked Crosses, and Medical Disease Inheritance.

Incomplete Dominance:

Incomplete Dominance is when one allele is not completely dominant over another allele. Here is an example: Yellow fur in guinea pigs is represented by: C^Y C^Y, White is represented by C^W C^W, and Cream is represented by C^Y C^W. Say a white guinea pig crosses with a white guinea pig, and produces all white guinea pigs. Cross a cream guinea pig with a cream guinea pig. Determine the phenotypic ratios.

Here's how you do it:

Simply use the foil method.

So then, you just convert the genotypes to phenotypes.

1 yellow : 2 cream : 1 white.

Sex-Linked crosses

Sex linked crosses are crosses that pass down traits through a sex chromosome.

Here is an example of a problem: 

Red  eyes is dominant over white eyes.

Red = R

White = r

Cross a homozygous red-eyed woman with a white eyed male.

Females are XX and Males are XY. Thus, because males don't have 2 X's, they can only have 1 half of an allele. Here is how you solve this problem:

So then you end up with 2 red-eyed females and 2 red-eyed males.

Medical Disease Inheritance

This has or so with blood types.

O, written as i, always is recessive.

A is written as I^A, AB is written as I^A I^B, and B  is written as I^B.

Blood type A can either be I^A or I^A i.

Blood type AB is the same as above.

Blood type B can either be I^B or I^B i.

Blood type O is I^O I^O or ii.

So here's a sample problem:

A mother has a blood type A, her daughter has blood type AB, and her son, blood type O.

What is the mother's blood?

Answer: I^A i, because without the i, then the son would never be able to have the blood type O.

That's it for this class.

Genetics Day 2

Today, we took a quiz on mono-hybrid crosses then went over di-hybrid crosses. This occurs when there are 2 genes involved in the cross. Here is an example of a di-hybrid cross problem. A heterozygous running, heterozygous white fur rabbit crosses with a homozygous running, homozygous brown fur rabbit. Determine the genotypic ratios. R = running r = waltzing. W = white w= brown. 

First, you can use Dr. Fitz's or Mr. Quick's way.

Here is Mr. Quick's way:

Then, you take each square from the left and combine them with all four from the right.

RRWw RRWw RRww RRww

RRWw RRWw RRww RRww

RrWw RrWw Rrww Rrww

RrWw RrWw Rrww Rrww

So the genotypic ratios would be:

4 RRWw : 4 RRww : 4 RrWw : 4 Rrww

Or 1:1:1:1

That was all for the di-hybrid cross class. 

Genetics Day 1!

Today, we were introduced to genetics and genetic crosses.

 

We only focused on monohybrid crosses today, as we will get to dyhybrid crosses next class. Basically, crosses are just methods of finding phenotypes and genotypes and determining which traits will show, which won't show, dominant and recessive traits, etc..., using a square.

 

Here's an example:

 

 

We worked on some practice problems then we took a quiz and that was it for the first class on genetics.

Lab Day

To start off class, we began by doing a white board based off of DNA structure. Mine looked as follows:

We then moved onto the lab.

Glow in the Dark Bacteria Lab

The purpose of the lab was to create bacteria with certain traits and to see which would display the glow of plasmid.

Here is out pGlo plus and minus tubes being heated. 

We found only one out of the four types to glow: LB with Amp. and Ara. 

Snork Day

Today we reviewed protein synthesis and took a quiz on DNA replication. 

After, we did a mini-lab where we determined the amino acids of complementary strands of RNA and were able to create features for our own snorks. 

My Snork looked like this

And here is a picture of the lab itself

Protein Synthesis Review Day

Today, we reviewed protein synthesis a took a quiz. The students taught the class, and went over the three categories: Transcription, RNA processing, and Translation. 

Here's what the board looked like when Mr. Quick explained the quiz answers:

We also looked at our pGLO labs and saw that most of the arabanose glow had gone out. 

That was it for the class before the test. 

DNA Structure Day

Today we took a quiz on the Journey of Man video, then we went over the structure of DNA.

Our white board looked like this by the end of class: 

As you can see, we drew the double helix  and labeled hydrogen bonds, nitrogen bonds, ATGC, and nucleotides.

Jump into the Gene Pool

Chapter 6 of Survival of the Sickest was about evolution that occurs inside our body, rather than the more popular view of outside evolution. 

It discussed how less than 3% of the DNA in our body is used to make proteins, and the rest (non coding DNA) comes from parasites that actually assist in shaping our evolution. 

Internal evolution is caused by slight mutations that, although most of the time are harmful, can sometimes result in beneficial adaptations for the body and then can be passed down through natural selection. Mutations are not random: they occur when the sequences of DNA change slightly, when the body is under stress. Jumping genes come in and delete or replicate genes to adapt to the stress, and this is when the sequences get changed and mutations occur. Our body changes its genes in hopes of beneficial mutations. Viruses, which make up some of the noncoding DNA, assist this mutations by grabbing onto areas in which the body believes are more likely for beneficial mutations. Once a beneficial mutation occurs, the body passes on the mutation through natural selection so that its offspring can have a higher survival and reproduction rate. 

Thus, through non-random mutations and the assistance of parasites, our body is able to evolve internally.