Today was by far the messiest day of the best lab of the year. We took our eggs out of the vinegar they had been bathing in for 24 hours. The goals for today: Weigh the egg, find a final volume of vinegar, take the shell off, place the egg with shell removed into corn syrup. Here were some pics from today:
Not ALLLL of our eggs survived the day though?!?!?!
If you weren't here today - I recommend you watch the following video!!
Next up - A couple more notes to give us enough content knowledge to at least BEGIN to understand what our awesome lab is about.
And THEN...... we met our egg!! This week we will be putting together the concept of Structure / Function of the cell membrane. Today you were given an egg. You named your egg..... you fell in love with your egg.... you weighed your egg and then........... you put it in a bath of vinegar. Here are some pics!
And then their was one named after me??? And they are now nice and cozy in their vinegar Bath!!
We had our first big exam on Tuesday and I was SUPER impressed with how you guys did!! Wednesday I didn't get a chance to see the morning classes due to the musical assemblies. Thursday you went through some intro book work and then worked on a couple daily questions. Today we did another set of daily questions and started into notes.
Here were the daily questions from yesterday and today
Notes for today:
I showed the simulated kidney cell filtering blood (which would make the liquid now simulated urine). I also showed you how the cell membrane "holds in" the cytoplasm.
For some classes we watched the beginning of this YouTube clip from Mr. Anderson at bozeman biology. He does a great job of making an analogy to the cell membrane. I stopped it once he started talking about the different proteins.
Today we used a practice test I created on study island as a review challenge. You can access the entire document either by going directly to study island,
( Username: First.Last@LHS Password: Student ID)
going into your biology class and opening that assignment
OR you can click on the image below and it will take you to a PDF of the exam with answers at the end.
Don't forget to look over the study guide that highlights main topics and terms from this chapter: You can access this document here:
Today we had a boat load of daily questions that served as a review of the lab yesterday and a deeper look at other factors that effect enzyme action. Here they are!
For the discussion around these and a few more - watch the video below:
I was really disappointing that we weren't able to do the lactase lab...... Now I know not to use glucose test strips that are almost 5 years past expiration!! BUT.... Alas.... I found the most ridiculous, hilarious.... but yet PERFECT description of the Lactase enzyme!!
And of course a little discussion from my man Hank!
Tuesday we actually had a chance to see the action of an enzyme. You entered the class to an interesting site for sure!!
I first gave a little introduction to Catalase. Catalase is an enyzyme found in nearly all living organisms. Its role is to break down Hydrogen peroxide (a natural by-product of certain metabolic reactions) into less harmful substances. First thing we did was write the reaction down (on your lab note card)
This tells us that with the enzyme catalase - for every two hydrogen peroxide molecules, 2 water molecules and one molecular (gaseous) oxygen is produced. Soooooo - We added Hydrogen peroxide to chicken livers. (While all cells contain catalase, liver tissue has a a high concentration of catalase) This is what happened:
Bubbles galore!! Watch the following video to see what happened and hear our discussion.
Next up... lets see if in fact what was left was just water: On your cards:
And............. this is what happened:
While we can't make a definitive conclusion that what was left was water - Knowing the reaction and products we can safely assume that the liquid that was left was NOT hydrogen peroxide (or it would have bubbled) Next was to test to see if enzymes were reusable: On your Cards:
We took the ORIGINAL piece of liver (that already degraded hydrogen peroxide) and added MORE hydrogen peroxide. If the enzymes had been used up, we would expect no reaction to occur. If they were NOT used up.... then the same thing should happen!! And that is exactly what we saw - BUBBLES GALORE!!!
Next was to test the effect of pH on enzyme activity. We added Vinegar (an acid) to our liver, let it sit and soak into the liver, then added hydrogen peroxide AGAIN. Our note card:
AND..... NOTHING happened. SOME of you had a very small reaction, but nobody had a full blown bubble fest like you did the first time. What does this tell us about the effect of pH on enzymes????!?!?! Did the enzymes "die".. NO (they aren't alive.) Did the enzymes disappear??? NO - they are still there - we already saw earlier that they are reusable. SOOOOOOOOO - what could explain no reaction??? THE ENZYMES SHAPE changed (specifically the active site) and therefore they were denatured!!! We will use our observation cards to do a detailed analysis of this on Thursday!!!
