Wednesday, October 10, 2007
Wednes-Day 1
Bio- we continued our discussion about cells and reviewed some of the key differences between prokaryotic (no nucleus) and eukaryotic (true nucleus) cells. We questioned why a growing cell must eventually divide or else die, focusing on two competing factors:
as a cell grows, its surface area through which nutrients are absorbed INCREASES (a good thing) BUT, as a cell grows, its VOLUME also increases, which may make it very difficult for the nutrients to get to where they need to go in the cell in sufficient time to keep the cell alive!
Which factor is more important as the cell reaches its critical peak size?
Answer and explanation, tomorrow.
By the way, here is a link to the site that shows a cell (of Paramecium bursaria, the green paramecium) that is so unusually large, that it is visible to the naked eye.
We conducted a lab investigating the effect of pH on the activity of the enzyme, CATALASE. You produce this enzyme in your own cells so that any hydrogen peroxide that forms via metabolic activities can be quickly catalyzed/converted/decomposed into harmless water and oxygen gas.
I noticed that all of you made observations that are consistent with what we know about enzymes, their shapes, and their resulting functions/degrees of activity.
Chem 7- we had our unit exam on Energy and Phase Changes.
Good to see that some of you took the test-taking advice that can only help you maximize your score. I want to see more people help themselves by consistently applying these techniques.
Your phase change and heat of fusion labs are due Friday and will be placed into your lab folders then; make sure that the labs are neat and complete! Check Blackboard for the map/outline and heating curve data for the labs.
We begin our new unit on Kinetics ( a.k.a. WHY things blow up), tomorrow.
Chem 8/9- we had our unit exam on Energy and Phase Changes.
Good to see that some of you took the test-taking advice that can only help you maximize your score. I want to see more people help themselves by consistently applying these techniques.
We then discussed/explained our two energy and phase change labs. These labs are due Friday and will be placed into your lab folders then; make sure that the labs are neat and complete!
Check Blackboard for the map/outline and heating curve data for the labs.
We begin our new unit on Kinetics ( a.k.a. WHY things blow up), tomorrow.
as a cell grows, its surface area through which nutrients are absorbed INCREASES (a good thing) BUT, as a cell grows, its VOLUME also increases, which may make it very difficult for the nutrients to get to where they need to go in the cell in sufficient time to keep the cell alive!
Which factor is more important as the cell reaches its critical peak size?
Answer and explanation, tomorrow.
By the way, here is a link to the site that shows a cell (of Paramecium bursaria, the green paramecium) that is so unusually large, that it is visible to the naked eye.
We conducted a lab investigating the effect of pH on the activity of the enzyme, CATALASE. You produce this enzyme in your own cells so that any hydrogen peroxide that forms via metabolic activities can be quickly catalyzed/converted/decomposed into harmless water and oxygen gas.
I noticed that all of you made observations that are consistent with what we know about enzymes, their shapes, and their resulting functions/degrees of activity.
Chem 7- we had our unit exam on Energy and Phase Changes.
Good to see that some of you took the test-taking advice that can only help you maximize your score. I want to see more people help themselves by consistently applying these techniques.
Your phase change and heat of fusion labs are due Friday and will be placed into your lab folders then; make sure that the labs are neat and complete! Check Blackboard for the map/outline and heating curve data for the labs.
We begin our new unit on Kinetics ( a.k.a. WHY things blow up), tomorrow.
Chem 8/9- we had our unit exam on Energy and Phase Changes.
Good to see that some of you took the test-taking advice that can only help you maximize your score. I want to see more people help themselves by consistently applying these techniques.
We then discussed/explained our two energy and phase change labs. These labs are due Friday and will be placed into your lab folders then; make sure that the labs are neat and complete!
Check Blackboard for the map/outline and heating curve data for the labs.
We begin our new unit on Kinetics ( a.k.a. WHY things blow up), tomorrow.
# posted by C @ 9:59 AM 
