WolbachiWhat??

This past week my AP Biology class completed our last lab of the year! Like all of our other labs this was a fun and interesting way to learn about something new! This week’s topic was… Wolbachia!!

What is Wolbachia?

Wolbachia is a common bacterium found in arthropods and nematodes. It is transmitted through host eggs and alters the host. In insects, Wolbachia is a reproductive parasite meaning it manipulates the reproductive biology of the host. Wolbachia is most vertically inherited but can also move horizontally across species boundaries. Within anthropods Wolbachia has four main ways of manipulating host reproductive biology, but you must also understand transmission. Wolbachia is not easily transmitted and is most commonly transmitted from mother to offspring through egg infection. Males can be infected but they do not transmit Wolbachia. The four ways are…

1. Feminization of infected males
2. Reproduction without males
3. Killing infected males
4. Cytoplasmic incompatibility- modifying sperm form infected males which results in embryonic defects and death when sperm fertilize eggs not also infected

Our Lab

The purpose of our lab was to collect data about infected insects around our area. Our class brought in various types of insects from many different areas to extract the DNA to test if any of the insects had Wolbachia. We first had to extract DNA from the insects using the abdomen because that is where the Wolbachia DNA would be if the insect was infected. There were many steps involved in this where we had to add substances and extract certain amounts to get the DNA out. Next we used PCR to see the DNA. Lastly to examine the DNA we added the samples to the gel electrophoresis. We let the gels run and compared it to the control and Allie’s insect, which we knew was infected.

In the pictures above you can see some people got results and were successful at extracting the DNA. Allie’s well had the insect with Wolbachia so you can see the band closer to her name is the insect DNA and the band further from her name is the Wolbachia DNA. Marissa, Jen, and Bharthi also got results, but all had insects without Wolbachia. Looking at Davis’ you can see she only had a band for Wolbachia DNA, which is very interesting because it means she extracted DNA, but there is nothing for the insects DNA, just Wolbachia.

This was a super fun and interesting lab. It took a lot of time and repeating steps, but was fun to do as a class and as our

Protozoan Lab

Check out the google slides presentation my group and I made after completing the Protozoan lab!

Mitosis: Counting Cells!

Purpose: The purpose of this lab was to observe the onion root tip to determine how long a cell takes in each phase of mitosis.

Introduction: Mitosis is cell division, which results in two identical daughter cells. Interphase is the longest stage and in this cycle the DNA replicates, the centrioles divide, and proteins are produced. The next phase is prophase and is the first mitotic stage. The nucleolus fades and chromatin forms into chromosomes. Chromosomes are made up of two chromatids with the same genetic information. In prometaphase the nuclear envelope breaks down so the nucleus is no longer visible. The spindle fibers begin to grow longer overlapping at the center of the cell. Next in metaphase, tension is applied by the spindle fibers and the chromosomes line up in the center of the cell. In the fourth step anaphase, the spindle fibers shorten which separates the chromatids. Lastly in telosphase the daughter chromosomes reach the pole forming two different cells.

Hypothesis: If an onion root tip is closely observed, then the majority of cells will be in interphase meaning interphase is the longest stage of mitosis.

Method:

1. Take three samples of an onion root tip
2. Take the first sample and focus on the tip under the microscope
3. Start by counting the total number of cells (an easy way to accomplish this is to count down and up and then multiply the two numbers to get an approximated value)
4. Count the number of cells in each phase and record the number
5. Divide the number of cells in each phase by the total number to get the percent of each one
6. Next multiply the percents found in step 5 by 24 to find the total hours spent in each cell.
7. Repeat steps 2-6 with the other two samples

Data:

Sample	Interphase	Prophase	Metaphase	Anaphase	Telophase
1	91%	4%	2%	1%	0.2%
2	92%	4%	2%	0.9%	0.5%
3	86%	5%	1.5%	0.6%	0.16%
Average %	89.7%	4.3%	1.8%	0.83%	0.29%
Time (hrs)	21.5 hrs	1 hr	0.43 hrs	0.2 hrs	0.06 hrs

Ebola: The Intruder of the Cell Signaling Pathway

Ebola is a very pressing issue in our world right now, and this project impacted me and broaden my education of the virus. I found this an interesting project and I want to continue looking into Ebola. This project will educate others on the effects of Ebola in our cells and body. It is important to continue making people aware of the issues of Ebola.

Some questions I still have are:

How long will it take to create a cure for Ebola?

Does Ebola kill bats or are they just the carriers of it?

Does Ebola affect people of different

Mine and Jennifer’s research on cell signaling:

Details of Ebola by my classmate Bharathi:

My Classmate Allie’s research on current research

Data of Ebola by Davis:

Disclaimer: I worked on this project with Jennifer Schulz

Chromatography

Chromatography is the process or technique to separate a mixture. In this case the lab was separating the pigments in different leaves. The molecules move up the paper at different rates because of the difference in solubility, molecular mass, and hydrogen bonding with the paper. The purpose of the paper was to show the separation of pigments and the purpose of the solvent was to move the pigments up the paper through capillary action. After chromatography the bands on the paper can be assigned a relative mobility factor (Rf), which is the ration of the differences of the substances’ distances. An Rf value is useful  to scientists because the value shows the different pigments using a value.

EQUATION:

Rf= distance solute traveled (D unknown)/ Distance traveled by solvent (D solvent)

The solvent front is the same as the D solvent and the shorter line that goes to the solute is the D unknown.   This lab helped identify and explain the different pigments and how the pigments affects leaves at a certain time of year. The pigments present in leaves are chlorophyll a or b, xanthophyll and carotene. These all produce a certain color which was seen on the strip. In the green leave there were three pigments present: chlorophyll a and b and xanthophyll (seen in picture below). In the experiment we started by getting the pigment onto the paper and then obseriving as the pigment spread out. In order to get the best results the paper needs to stay in the isoproyol acid for a while. The purple leaf had the carotene, chlorophyll a or b, and xanthophyll all present in the leaf.  The purple leaf clearly had little production of chlorophyll compared to the all green leaf.   In the pictures below the pigment is spreading out as the paper sits in the alcohol.

 

In this video the experiment conducted is similar to the one performed in the pictures above. They both demonstrate the different leaf pigments and why leaves change color in the fall.

I would like to know what else chromatography can be used for.

Video from youtube All pictures except for the equation taken by me “Leaf Color Chromatography – Bite Sci-zed.” YouTube. YouTube, n.d. Web. 06 Oct. 2014. <https://www.youtube.com/watch?v=qH-AJDqsSII&gt;. http://www.assignmentpoint.com/wp-content/uploads/2013/03/rf.jpg