Vaccine and Neon Bacteria

For the first part of the lesson, we talked about vaccines. Basically, vaccines are weakened virus. If these non-sickness-causing virus are injected into human body, the white blood cells will memorize thee virus' protein coat, and the next time when the white blood cells encounter similar virus, they would be able to recognize it and fight it off.

Usually, what virus do is to hijack cells and provide RNA and have the cell produce new virus.

For the second part, we did a lab, in which we can genetically change bacterias. Basically what we did is to have two samples of bacterias, in sample one we added a plasmid DNA that would allow the bacterias to glow and be immune to antibiotics. We didn't add anything to sample two. We prepared two agar plates for each sample. For sample one, one plate contains arabinose (I looked up online, this switches on the DNA that allow bacteria to glow) and both contains ampicillin. For sample two, one plate contains ampicillin, the other one doesn't.

Our prediction is that bacteria in sample one plate without arabinose will grow but won't glow. The other sample one plate bacteria will grow and will glow. Bacteria in sample two with apicillin won't grow. Bacteria in sample two without ampicillin will grow but won't glow.

Jump Into the Gene Pool

Only 3% of DNA are coded for building cells and the other 99% were once called "junk DNA"because people think they don't do anything. Recently, they are renamed as noncoding DNA because people find out that they do have their significance. McClintock found out that when organism is under harsh environment, its gene would have an intentional mutation. The genomes that switch place and cause mutations are called jumping genes. This intentional mutation is the organism's attempt to come up with a beneficial mutation to help it overcome the harsh environment. After that, natural selection kicks in and decide if this mutation would allow the organism survive and therefore evolution happens. It was found out that more than half of the noncoding DNA is made up with jumping genes, which correspond retroviruses' DNA. Scientists think that the human DNA allowed the virus genes to hitchhike. in return, the virus genes help human to evolve faster.
Here's my mind map. I also put it on my blog:
  https://sites.google.com/site/randombiocrap/home/jump-into-the-gene-pool-reading-assessment

DNA

We learned about DNA structure in class. DNA is made up with nucleotides, which are made up by a phosphate, a sugar and a nitrogen base. The tie between the phosphate and the sugar is a phosphodiester bond, and the bond between the sugar and nitrogen base is a hydrogen bond, including bonds between A-T and C-G. A and G are called Adenine and Guanine, which are Purines. T and C are called Thymine and Cytosine, which are Pyrimidines. There are 2 bonds between A and T. 3 bonds between G and C.

Journey of Man and DNA...

For the video, "Journey of Man", that we watched in class, it said that human beings originated from Africa. In order to prove that, scientists went to all parts of the world and look for people whose DNA contain traits of the direct ancestor whose offsprings developed different traits that led to the formation of different races. They found these people, and found out that their DNA and looks resemble people of different races.

For the DNA reading questions:
1. Mendel's pea breeding proved that although some DNA information is not visible in the plants' physical traits, it still exists and might show in the plants' offsprings' physical traits.
2. Watson and Crick

3. First, point mutation. A single base pair changes. For example, if a whippet dog has a point mutation, it inactivates the "stop" sign for muscle growth, and the whippet dog will develop extra muscles.

Second, insertion. A number of bass-pair structures are inserted in the genes and make differences. For example, some bass-pair structures are inserted in the genes of pea and causes its skin to wrinkle.

Third, gene copy number. A section of genes can be copied more than once due to error and causes variations. For example, chimpanzee only has one gene for starch-digesting enzyme salivary amylase, while human has more than 10.

Fourth, duplication. sequences repeat. For example, if a certain sequence of pig's genes repeat, the pig will have dark patches on its skin.

Fifth, regulatory changes. Mutations in the DNA that controls activation can change. if this happens to corns. Two kinds of corns will emerge: bushy ones and tall ones.

4. Study that focuses on the effects of changes in important developmental genes and the roles they play in evolution.

5. If human beings migrate to a place that suits milk-producing, their milk-tolerance will arise in order to adapt to their food. It shows how culture can influence evolution.

One Page Response

One Page Response

            From the “Journey of Man” video and reading, I learned that the ancestor of human beings originated from Africa. They migrated over time and populated the world. The process of migration is extremely slow. Rather than migration, it is more like some of the ancestor population moved a few miles away from the others in order to have more space and food sources. After millions of years, generations of ancestors kept moving away from each other, and they eventually reached all parts of the world. How can we prove that all human beings around the world originated from Africa? By comparing the mtDNA and Y chromosomes of human beings all over the world, scientists trace the similarities and find out that all females have one ancestor and all males have one ancestor. As a result, the origin for human can be traced back to Africa. For my assigned reading, I read “Founder Mutation”. The term referred to a genetic legacy of a common ancestor that can lead its offspring to disease. If a person receives a certain founder mutation gene one side of his parents, he would not get the disease. Instead, he would be a carrier, and being a carrier of founder mutations can prevent him from getting certain kinds of disease. However, if a person receives a certain founder mutation gene from each of his parent, he will catch the disease and will probably die before reproduction. As a result, those who carry a pair of founder mutation genes will die out, and those who carry only one founder mutation gene will benefit from the gene and will pass it to their offspring and control the proportion of the founder mutation gene in a population. I think this is the reason why close relative cannot marry each other. If they do, there will be more chances that their offspring will carry a pair of founder mutation genes and die of disease. Furthermore, it will throw off the founder mutation gene proportion balance in the population.

            The founder mutation gene shortens after each generation because clean genes will be added in when reproduction takes place. Therefore, people can find out when the common ancestor lived according to the length of the founder mutation gene. Other than that, the founder mutation migration provides proof for human migration. It provided evidence that human ancestor—Homo sapiens did not interbreed with other human groups. Accordingly, we can be sure that the modern human directly evolved from Homo sapiens. This also resolves the question asked in “Journey of Man” article: if the Native Americans evolved from early human groups other than Homo sapiens. 

CLARIFIED

I am able to correct my mistakes because i just cleared up two concepts through my study for the test:
1. p and q are not the percentage. they are FREQUENCY.
2. The reason why the percentage for heterozygous population is 2pq instead of "pq" is because the genotype can be either Aa or "aA". It can be A from father and a from mother or a from father and A from mother.

Hardy and Weinberg Equation

p^2+2pq+q^2=1, p+q=1, p^2=AA genotype population percentage, q^2= aa genotype population percentage, 2pq= Aa genotype population percentage. p=dominent allele frequency, q=recessive allele frequency.
The population's allele and genotype will remain constant from generation to generation when:
1. The breeding population is large
2. Mating is random
3. There is no mutation of the alleles
4. No differential migration occurs
5. There is no selection
If the above do not occur, evolution will not take place, alleles frequencies will remain unchanged.

Evolution is the sum total of genetically inherited changes in the individuals who are the members of a population's gene pool.

Natural Selection

Following up to the brine shrimp lab, we made a graph for the data.

The percentage of surviving brine shrimp reaches its highest when the percentage of salt is 0.5%. It shows that the sample of brine shrimp that we used is best adapted to 0.5% salt water. This lab shows that brine shrimps that can adapt to the environment will survive and pass down their genes, so that the next generation will have these genes that helped them survive. In that way, species evolved to have these genes, which is the process of natural selection. 

Other factors that could have influenced the results can be temperature, season, chemical in solution, pH level, sun exposure, type and amount of brine shrimp.

We also did the "tiger lab." 

We have red beads to represent dominant alleles and green beads as recessive alleles. Red means alleles that give tiger fur and green means alleles that give tiger no fur. Tigers with fur will survive to reproduce and tiger without fur will die off. In the end, all "tigers" left had fur. They are carrying either HH or Hh genes. 

If tigers with HH genes reproduce, they will have HH offsprings. If HH and Hh reproduce, they will have HH or Hh offsprings. If hh and Hh reproduce, they will have Hh or hh offsprings. If hh and hh reproduce, they will have hh offsprings. 

Eventually, hhs die off and there comes natural selection.

The only way to have other hh is through emigration or immigration.

Parents Day Stuff

So... We read three articles about how human prefer symmetrical faces, average faces and feminine faces. Human beings like symmetrical faces because these faces are easier for their brains to process.
Animals prefer to mate with those that possess sex-typical physical traits because it shows that they have the ability to reproduce. However, a lot of female human beings prefer males that posses female facial characteristics. This is because both human parents participate in raising their off springs, so females think that males with feminine characteristics are more likely to be "good parents."

Species Variations and Brine Shrimp

Mr. Quick brought a bunch of "illegally gathered" shell and asked us to sort them. My group decided to sort them according to their shape. There are two kinds of shapes. Some of them are pointy, and others are flat. After that, Quick asked us to sort them in a different way, so we sort the shells according to their sizes. We had a pile of big ones, a pile of small ones and a pile of medium size ones.
The reason why each specie has so many variations is that it develops characteristics which enable itself to survive. Species develop different sizes, colors and shapes. Some of these mutations are positive, some are negative and some are neutral. All of the mutations that survived will be passed down to the next generation.

Now, about brine shrimp.

We prepared 0%, 0.5%, 1%, 1.5% and 2% salt water and put brine shrimp eggs into salt water.

We went back to count the number of brine shrimp that hatched after 24hrs and 48hrs. In the end, the hatching viability for 0% salt water is 0%, for 0.5% is 25.81%, for 1% is 11.11%, for 1.5% is 16% and for 2% is 39.39%.

(My lab partner)