Mitosis notes

Jellies (and Squids if you want them)- There is a new PDF of the mitosis slides with notes added, since I was out for the lecture yesterday.  Review them over the weekend and I will clear up any questions on Monday.

For everyone- continue working on your osmosis lab final.  Email me if you have questions (I won't be checking comments on the document until I grade the finals).

Squids- Finish up the stem cell activity if you didn't finish it in class.

In class work Wednesday Dec 17

Good morning Jellies,

I am out sick today. In class you should do your best to fill in the Mitosis notes found in the Unit 2D folder. You can use the reading (mitosis reading, 2D folder) or other online sources to help you. The most important part will be recognizing the phases of mitosis- the reading has some nice pictures. We will do a lab tomorrow and then fill in any gaps in your notes next class. Be sure to do the activity on the last slide (only takes about five minutes). 

Mitosis homework

Homework after the mitosis (PMAT) lecture: finish the mitosis reading on the stages of mitosis.  Continue to work on lab final (due Tuesday).

Monday night HW

Read pp 82-84 in the mitosis reading found in the unit 2D folder.  You should continue working on your lab final as well- those are due next Tuesday (last day before break).

Link to HHMI cell cycle page: http://www.hhmi.org/biointeractive/eukaryotic-cell-cycle-and-cancer

Misconception

As I read through your introductions I am seeing a common misconception, that the reasons ions can't get across the cell membrane is due to the charged phosphate group.  This might be a small factor, but the main barrier to ions are the hydrophilic tails.

I think the problem may be due to the way the phospholipid bilayer is drawn, like below.

From this diagram it looks like the hydrophilic portions are large and act as a barrier.  But in reality the phosphate group is pretty small compared to the hydrocarbon chains.  Below is a space-filling model (closer to the real structure).

Here you can see that that portion is fairly small.  

So, to summarize, if you are going to discuss why ions can't cross the cell membrane your primary reason should be that they can't get across the lipid portion.

Weekend HW

-Make sure you have completed the notes on Lessons 17-20 (17 and 18 we did in class.  If you are doing these on your own, note that we only did the last third or so of lesson 18).

-Answer the questions on the strawberry lab and share in your folder.  If you didn't do it in class you can do it at home- it only takes 10 minutes and everything you need you can get at the grocery store.  Use rubbing alcohol for the ethanol and an unfolded paperclip for the extraction loop.

-Read and take notes on the DNA replication reading in the 2D folder.  Pay attention to the steps of replication as well as the purposes of the three enzymes helicase, DNA polymerase and ligase.

Here is a really good animation of DNA replication (but unfortunately it doesn't work on iPads).  Don't worry about the RNA primer or about any of the enzymes besides the three we discussed in class.

**ALMOST FORGOT!!***  I am in the process of giving feedback on your osmosis labs.  Jellies are all done.  Squids, I will be done with yours by the end of the day today.  Finals are due Dec 23rd.  Remember to check the rubric in the Unit 2C folder.

Wed night HW

If you have access to a laptop or desktop, finish up your notes through the end of Lesson 19.  Then do the following:

Read the Wikipedia page on Rosalind Franklin.  Hers is a famous story in science about the failure to recognize the work of all contributing individuals as well as the sexism that was common and accepted at that time.  

Note: James Watson, one of the two scientists described in this lesson, worked as director, president and chancellor at Cold Spring Harbor Laboratory (the institution that runs the dnaftb.org site) for nearly 40 years.  This may explain why there is no hint of controversy over Franklin’s contribution in Lesson 19, although nearly all other publications at least mention this in passing.

HW after quiz

The link to the page with the animations is here.  Remember that the animations do no work on the iPad.  Additional information about the three experiments we looked at in class can be found here.

For homework, read this page which summarizes the work of Watson and Crick to elucidate the structure of DNA.  We will look at that animation (lesson 19) in class.  I highly recommend using printfriendly.com to convert the webpage into a PDF that you can bring into Notability to take notes on.

Transport Across the Cell Membrane Quiz Next Class (Mon/Tues)

Like the last quiz, you may bring in one 3x5 index card that has handwritten notes on one side. Squids- I forgot to give you cards.  You can bring in your own or just use a 3x5 piece of paper.

The quiz will cover all types of transport and include a few questions about cell organelles.  I would read over the organelle notes in the folder but I wouldn't dedicate a ton of time to organelles.  If you have the opportunity, studying together is a good way to check your understanding of the material.

The quiz is only 28 multiple choice questions.  We will start the next topic as soon as the quiz is done.  

Osmosis Lab write up

Draft of the Introduction and Results section due on Friday.  More detailed information will be in the Unit 2C folder, as well as sample papers.

Osmosis Lab

Jellies- make sure someone in your group emailed me a list of materials/equipment needed by 2:30 today (Monday).  If its not on the list, you won't have it for your lab!

HW is to come up with a list of procedures so that you know what to do when you come in tomorrow.