Evolution Arms Race

As we continue to learn about microevolution, we watched PBS's Evolution Arms Race.  Students answered guided questions and wrote their own questions which we used for a discussion.



When we return from Academic Travel we will be shifting our focus from microevolution to macroevolution.

How populations evolve

Today we brainstormed ideas about some of the evidence that validates the evolutionary view of life.  For part 1 of your homework: look up information on the four key terms on the first page of the packet.  What does a person study if they are in the field of comparative embryology?  What is an example of a homology?  What do homologies tell us about the relationship between species?

Darwin proposed natural selection as a mechanism of evolution, as it turns out there are four parts of evolution.  However, since your book starts with Natural Selection, that's where we will begin.


To see natural selection in action we read a case study about microevolution in a specie of crickets in Hawaii.

Attack of the Mutant Crickets!!!

"Attack of the flesh-eating parasitoid maggots!! Mutant mute crickets run rampant in tropical paradise!! The headlines may sound like a trailer for a cheap horror flick — but in fact, these sensationalist sound bites accurately describe the situation on the Hawaiian island of Kauai. The "flesh-eating parasitoid maggots" are the offspring of the fly, Ormia ochracea, which invaded Hawaii from North America, and the mutant crickets are the flies' would-be victims. The flies follow the chirps of a calling cricket and then deposit a smattering of wriggling maggots onto the cricket's back. The maggots burrow into the cricket, and emerge, much fatter, a week later — killing the cricket in the process. But this fall, biologists Marlene Zuk, John Rotenberry, and Robin Tinghitella announced a breakdown in business-as-usual in this gruesome interaction: in just a few years, the crickets of Kauai have evolved strategy to avoid becoming a maggot's lunch — but the strategy comes at a cost... " Want to read more or see the article with color photos? Click here.

If you did not finish your summary of the case study in class you need to do that for homework as well.  Not sure where to start for you summary, think of how this case study is an example of natural selection.

 Lastly, define the terms/concepts on page six of the packet.  

Test Review

Today students created their own jeopardy review questions on the DNA structure and replication, as well as transcription and translation.  We used the mini whiteboards for each pair to write their answers down.    Next week we will begin learning about evolution. As we do this, remember this cartoon:

Your test has the following question types: multiple choice, fill in the blank, true/false, short answer and one essay.

Transcription & Translation Worksheet

For homework, G period should finish the worksheet from class today.  The codon chart is on page 303 in your book and it is also posted below.

C period: We reviewed in class today and G period we will review tomorrow for your test on Friday.

Expanding on Transcription & Translation

Today we continued our work on Transcription & Translation.

G period homework:  complete the worksheet (both sides).  The colors you use do not matter, so long as you are consistent.

C period homework: complete the transcription and translation sheet from class today. HINT: rRNA is the  RNA component of a ribosome.

Transcription & Translation

Today students had a homework quiz on the basics of transcription & translation.  After the quiz we went into more detail about how the process works.

Homework: Complete the worksheet (front and back).  Be sure to take care in using complementary base pairs for the DNA strand.  The colors you use don't matter, so long as you are consistent.

Reminder: You will have a test on DNA structure, replication and transcription / translation on Friday.

Homework for the Weekend

Today in class you made some great posters to review the structure of DNA and how DNA replicates.  Here is your homework for the weekend:

You will be learning about transcription and translation.  You have a choice in how you learn this information.

You can:

* Read pages 300-306 in your book
* Play this game from Utah Genetics
* Watch this video from the DNA Learning Center (more advanced)

You should take notes because you will have a short quiz in class on Monday (or Tuesday for G period).

DNA Replication

Today we started DNA replication.  We used this animation to help us learn the basics and it is what you need to complete the homework.

Watch the Mechanisms of DNA replication below.  Without the sound can you identify which is the leading strand and which is the lagging strand?

Gel Electrophoresis Pictures

Today G period practiced using gel electrophoresis and got great results! After practicing micro-pipetting and learning how to read the 2-20uL and 20-200uL pipettes, students were ready to decide what color (or mixture) of colors to load in their gels (the ideal volume for the wells is 8uL). Check out the pictures of the set up below.

Materials for the lab (and our class mascot).

A gel loaded and ready to be run.

The new BioRad Power Packs are amazing!  We ran two gels at a time for 18 minutes, at 300V and had great results.

Even after only two minutes, you can start to see the green dye in lane 1 has separated out into blue and yellow dye.

A finished gel after 18 minutes at 300V.

Notice how the black food coloring is actually made out of orange and purple dye.  Can you determine which molecules of dye are the largest and which are the smallest?

Marcela records her results.

Antonia and Milly record their results.

Gel Electrophoresis

Today students learned how to use micropipettes as well as how to run gel electrophoresis.  Tomorrow's post (from G period) will have pictures and a more in depth summary of the lab.

There is no homework tonight :)

Strawberry DNA Extraction

Today we extracted DNA from strawberries and had great results!

C period Homework:  Complete the gel electrophoresis virtual lab. Click here to link to the virtual lab.  Take notes on gel electrophoresis.  You will have a short reading quiz on Friday before we actually do gel electrophoresis.

G period: No homework (unless you want to do the virtual lab, so you don't have homework on Thursday night).