DNA fingerprinting!

Starting out with Mr. Jimmy Sweet and his obsessively cleanliness, noticed something was disturbed in his room.  He noticed his NOVA lollipop had been broken into and now was "worthless".  Someone had broken into his room and tasted his never-opened lollipop.  He has seven suspects; his sisters, Candy, Cookie, Sugar, Lolly, Honey, Brandee, and Carmela..quite the names right?? Well anyways, they have been spotted and are now in Jimmy's custody, as he begins his finger printing for DNA!
The Process
To start the process of finding his culprit, I poured restriction enzymes into the DNA.  The restriction enzymes are kind of like scissors, snipping the long DNA molecules at different locations.  Wherever those cuts occur depend on the code that goes along with the DNA molecule and the code within the enzymes.  Our next step was pouring agarose gel into a tray on the lab counter.  The agarose gel is thick and resembles Jello.  It represents a molecular strainer, allowing tiny pieces of DNA to navigate through more easily than large pieces.  Then, we poured the DNA into the tray with the agarose gel.  It made a hole in the gel and all of the DNA pieces lay in that hole.  After that we had to flip the switch on the tray with the DNA and agarose gel.  This began electrophoresis, which is the process of moving molecules with an electric current.  The DNA pieces have a small negative charge, so they move towards the positive end of the tray.  However the gel acts like a strainer.  Smaller DNA fragments move through the gel easier and farther toward the opposite end of the tray than the bigger ones.  When electrophoresis is finished, the little pieces are distributed in the gel according to their lengths.  After electrophoresis we placed a nylon membrane on top of the gel.  Due to the difficulties of the agarose gel, DNA is transferred to a nylon membrane, which looks like a sheet of paper.  The DNA got sucked up into the membrane as liquid traveled up from the gel towards an absorbent material that had been placed over the membrane.  I then added probes to the membrane in the tray.  The probes are bits of DNA that have been labeled radioactively.  These little guys attach themselves to the DNA pieces on the nylon membrane.  However they only attach where their code came upon a sequence of code with the many fragments.  All of the extra probey stuff that didn't attach itself to DNA gets washed away.  The next step is to put a X-ray film on top of the nylon.  The radioactivity that comes from the probes, which are only at a minute number of locations on the membrane, shows connecting areas on the X-ray film.  After the probes show up on the X-ray you place the film into the developer.  After it is developed the X-ray film shows locations on the nylon membrane where the probes got attached to the DNA pieces, finally giving us the fingerprint! :)
Now on to the matching game!  Out of his seven sisters, he has to find the one that took his one of a kind NOVA lollipop!  After carefully looking and deliberating, we figured out that Honey Sweet was the criminal!  Jimmy decided that Honey has to be denied dessert which is Macadamia Rum Baked Alaska-yuck!
After finding out this information, we have learned that DNA fingerprinting, can be a typically easy process, if you know what you're doing anyways; and surprisingly enough i do :)


Source 1:
http://www.pbs.org/wgbh/nova/sheppard/labwave.html


Wrongfully Convicted
DNA has helped us in many different ways from matching parents, all the way to helping solve criminal cases.  In Ronald Cotton's case, he was wrongfully convicted for rapes on August 1, 1984.  In January 1985, he was convicted by a jury of one count of rape and also a count of burglary.  He was sentenced to life plus 54 years.  Although Cotton's alibi was supported by family members, the jury wasn't allowed to hear evidence that the second victim had failed to pick Cotton out of either a police lineup or a compilation of pictures.  The conviction was based on many reasons like a photo id being made by one of the victims, a police lineup id was also made by a victim.  A flashlight in Cotton's home was also resembled the one used by the burglar.  The rubber of Cotton's shoe was also used due to it's match with rubber found at one of the crime scenes.  After all of the drama, Ronald Cotton's attorney filed an appeal.  The North Carolina Supreme Court flipped the conviction because the second victim had chosen a different man from the lineup and the trial court didn't allow for this to be told to the jury.  In November of 1987, he was retried, for both rapes.  The second victim decided that Cotton was the assailant.  Before the second trial, a man in prison, who had been convicted of almost identical assaults, told another inmate that he had committed what Ronald Cotton did.  The judge refused to let the jury hear this also and Cotton was sentenced to life for both rapes.  Finally after many years DNA was used to help prove Cotton's innocence.  The samples from on victim or too old to be used, but the other victim's DNA swabs were given to PCR test and showed NO match to Cotton.  With a request from the defense attorney, the results were then sent to the State Bureau of Investigation's DNA data base containing the DNA patterns of convicted, dangerous felons that were being held in North Carolina prisons.  The state's data base brought up a match with the convict who had recently confessed to committing the crime.  After Ronald's attorneys received DNA test results in May of 1995, they got ahold of the district attorney, who joined the defense attorneys in order to dismiss the charges.  Finally on June 30, 1995, Cotton was finally cleared of all charges and released from prison.  In July 1995, Cotton was eligible for $5,000 compensation from the state of North Carolina after he had served 10.5 years of a wrongful conviction.

Source 2:
http://www.pbs.org/wgbh/pages/frontline/shows/dna/cotton/summary.html

Can you identify the bacteria?!

While doing the virtual lab, I was a little confused at what we were supposed to be doing and so I just followed through the motions without a clue.  After doing it I quickly learned I was soon to be identifying some type of bacteria.  After going through all of the steps I learned the bacteria I was dealing with was Bartonella henselae.  Many species of Bartonella able to cause disease in humans are transmitted by a vector, or directly from an animal reservoir.

Common Bartonella sicknesses

• B. bacilliformis by sandflies causes Oroya fever. 
• B. quintana from body lice causes trench fever
• B. henselae from cats causes cat scratch disease (CSD)
• it generally reveals as lymph glands swelling, possible skin lesions at the site of inoculation and may be joined with fever, fatigue, and other symptoms.
• Patients can be susceptible and and develop a different disease called bacillary angiomatosis, caused by infection of B. henselae or B. quintana.

Picture of Bartonella henselae:

Cat Scratch Fever:

Source: http://www.hhmi.org/biointeractive/vlabs/bacterial_id/index.html

Eugenics

What is eugenics?
Well in order to get this thing started, I guess I should find out what the term eugenics actually means because I honestly have NO clue!  Well let's get to it! Eugenics is a theory that means humans can influence our own evolution, through selective breeding or genetic enhancement.  People usually have a negative attitude towards eugenics because your basically picking what you want your child is going to look like, causing many people to disagree.  Eugenics in America developed in the beginning of economic and social problems for American industry.  Eugenicists discussed that society paid a costly amount by allowing the birth of disabled people who would need care from the state.  People saw eugenics as an attempt to solve all of the problems the U.S. was facing because it helped the cause in the defective germ plasm of society itself.  Eugenics offered a prospect of planned, slow, and smooth transition to a more harmonious future.  It gave life the biological counterpart to new theories in control and rational management in business.  It also provided an objective, scientific approach to problems that used to be called too difficult and it promised to attack social problems at their roots.  Eugenics said that disabled people should be prevented from mating, through custody in asylums and compulsory sterilization.  The papers on polygenic inheritance caused problems that effected the criticisms for the research of eugenics.  The data for the eye color paper came from school principals and other friends.  The uncertainty in the different descriptions of discrete eye coloration gathered by so many different collaborators caused struggles during data analysis.   Eugenics impacted America by coming up with marriage laws, sterilization laws and immigration restrictions!  Immigration restrictions were placed to prevent convicted criminals, the poor, and mentally sick from coming into the country.  Overall, Eugenics can be perceived in many different views, through all different eyes.  Some people may think it's bad, but some people think it's good for our country. So what do you think?

Here is the site where I got all the information from :)
http://www.eugenicsarchive.org/eugenics/

What in the world is Meiosis?!

Well to start with meiosis is a type of cell division in which the eggs and sperm are produced.  Meiosis includes a lowering of the genetic material.  Meiosis is made up of two successive nuclear divisions with only one round of replicating the DNA.  The four stages of Meiosis are interphase, prophase, metaphase, anaphase, and telophase, but it happens twice!  Here is the stages in a little more detail!
Interphase- This is before meiosis begins and genetic material can be doubled.
The first division of meiosis starts with prophase 1, which is when duplicated chromatin condenses.  Every chromosome is made up of two, closely related to sister chromatids.  Crossing-over is possible at the end of this stage.
Metaphase 1 is when homologous chromosomes line up at the equatorial plate.
Anaphase 1 is the time at which the homologous pairs separate with sister chromatids remaining attached.
In Telophase 1 two daughter cells are made with each daughter that includes only one chromosome of the homologous pair.

The second division of meiosis is when the gametes form.  It starts with Prophase 2; this is where DNA does not get replicated.  In Metaphase 2, chromosomes line up at the equatorial plate.  During Anaphase 2 centromeres divide and the sister chromatids move separately to each pole.  At the Telophase 2 phase cell division is finished.  Four haploid daughter cells are collected.

One parent cell produces four daughter cells.  There is only half the number of chromosomes in the daughter cell that are found in the original parent cell.  If crossing over occurs, they are genetically different.
Meiosis is different from mitosis because there are two cell divisions in meiosis which ends in cells with a haploid number of chromosomes.  Overall meiosis, is a very drawn out process and can be complicated to most people, but once you get the just of it, it makes a lot MORE sense!

All of the Meiosis Steps!

This is the site where I got all of my info from!!! :)
http://www.accessexcellence.org/RC/VL/GG/meiosis.php

My Self-Reflection and Goals! :)

For this semester I would like to learn more about genetics and the forming of a baby!  Since this is the last of my junior year I would love to pass this semester with a high B or A :) I've actually learned a lot in college biology even though the first quarter was mainly all about facebook because i just couldn't concentrate whatsoever!  But thankfully in the third quarter I'm doing a little better.  However I need to get my rear in gear and catch back up on all of my posts darn it!  :) Well that's all I have to say for now! :)

Mitosis! :)

In the Mitosis process, there are six stages starting with interphase.  Interphase is where the chromatin is undifferentiated in the heavily-stained nucleus.  Before a cell begins mitosis, it has to undergo a synthesis phase where every chromosome is duplicated and is made up of two sister chromatids joined by a specific DNA sequence known as a centromere.

The first initial phase of mitosis is called prophase.  The nuclear chromatin starts to be organized and forms into thick strands that eventually become chromosomes.  During this stage, the cytoskeleton begins to break down and the main piece of the mitotic apparatus, the mitotic spindle begins to shape outside the nucleus at opposite ends of the cell.  

early prophase

The next phase is metaphase, or the middle of all the stages.  Metaphase is when the chromosomes, attached to the "kinetochore microtubules," begin to align in one plane halfway between the spindle poles.  The microtubules apply a pull on the chromosomes and the entire spindle-chromosome complex is ready for the next phase.  In metaphase, the kinetochore and polar microtubules are clearly seen and radiate out the ends of the cell which leave the chromosomes in the middle of the complex.

metaphase

After metaphase, the cell begins anaphase.  After the metaphase chromosomes are aligned at the metaphase plate, the two halves of chromosomes are pulled apart by the spindle apparatus and move to the opposite spindle poles.  As the chromosomes are pulled toward the poles the kinetochore microtubules shrink, while the polar microtubules lengthen to assist in seperating.  Anaphase is the fastest stage in mitosis.  

Anaphase

The last stage of Mitosis is called Telophase.  In this stage, the daughter chromosomes arrive at the spindle poles and are finally redistributed into chromatin.  Cytokinesis also continues through telophase.  After the chromosomes are completely separated and their extrusion to the spindle poles, the nuclear membrane begins to reform around each group of chromosomes at the opposite ends of the cell.

Telophase

Overall Mitosis is a fairly long process and at the end it results into two daughter cells.  The process then starts all over again.
http://micro.magnet.fsu.edu/micro/gallery/mitosis/mitosis.html

Enzymes Reactions Lab!

A couple of weeks ago we did a lab about enzyme reactions.  We tested the levels of pressure when yeast was mixed with a variety of different mixtures.  In the first graph shown we tested the levels of pressure with 5 droplets of yeast, 20 droplets of yeast, and 45 droplets of yeast.  The mixture that had the highest slope of pressure was the one with 20 droplets of yeast.

In the graph to the right, we measured the levels of pressures of yeast mixed with different levels of pH.  The enzyme reaction was the highest with a pH level of 4.

  The graph on the left shows pressure with different temperature levels.  We experimented with yeast and water mixed at room temperature, cold temperature, and hot temperature.  According to our observations the yeast had the most pressure at hot temperatures.