Wednesday, May 7, 2014

Assignment for 5-8-14

Watch the video at the following link and use it to answer the questions that follow.  Be prepared to discuss your answers with the class.

Cell Transport

Explain why saltwater fish cannot live in fresh water and why freshwater fish can't live in saltwater.  In your answer, use terms such as hypertonic, hypotonic, isotonic, diffusion, and osmosis.




Dikscuss two situations in which facilitated diffusion would be used instead of simple diffusion.





If passive transport does not require energy expediture by the cell, where does the energy come from that moves the molecules?






Answers

1.  Saltwater fish cannot live in freshwater because the freshwater would be hypotonic to the fish.  Since there is more salt in the fish water would move in by osmosis causing the fish to swell.  Salt would diffuse out in an effort to reach equilibrium.

Freshwater fish cannot live in saltwater because the saltwater would be hypertonic to the fish.  There is a higher concentration of salt in the water than in the fish.   Therefore, the water would leave the fish by osmosis resulting in the cells of the fish becoming dehydrated.

2.  If molecules are too big to pass between the phospholipids but small enough to fit through a protein channel, they could use facilitated diffusion.  Molecules the size of sugar or amino acids would have to do this.  Also, molecules that are polar or have a charge would have to use a protein channel because they cannot get past the lipid tails of the phospholipids.  Water and ions would have to use this method for this reason.

3.  The molecules have their own energy.  They are constantly in motion, and when they collide, they transfer energy to one another.  Therefore, this motion is due to the energy the molecules themselves contain and requires no energy expenditure of the cell.

Thursday, April 17, 2014

Tuesday, February 11, 2014

Link and Instructions for Punnett Squares Activity

The following is the link to the program you will be using for today's activity.  Click "Run" when prompted.  Follow the instructions on you handout and on the screen.  Draw the Punnett square in your notebook with arrows and instructions as prompted on the handout.  If you finish all parts of the first activity, you may go on to the second part with the definitions.

Punnett Square Activity

Friday, December 20, 2013

Bonus Point Opportunity

Watch the rap battles video at Rap Battles in Science Watson and Crick vs. Rosalind Franklin.

Complete the assignment provided on the handout given in class.

Use the following links to help you find information on the history being portrayed.

Discovery of DNA
Rosalind Franklin Biography
The First Discovery of DNA
Linus Pauling's DNA model
Maurice Wilkins DNA from the beginning

Monday, September 9, 2013

Genetics Terms Modeling Assignment

Post your analogies, stores, etc. here.  Cartoons will be uploaded and posted in the Awesome Student Work Section.  When posting your stories, post as a comment.  I will have to read your comments before they will be fully published on the site.  MAKE SURE TO INCLUDE THE NAMES OF EVERYONE WHO WORKED AND DESERVES CREDIT IN YOUR GROUP WHEN YOU POST THESE.

Tuesday, May 21, 2013

Welcome Incoming Sophomores

Welcome to Biology. I am looking forward to working with all of you in the upcoming year. Posted here are several links you will find useful next year. Please download and read the syllabus paying close attention to the grading policy. I have also posted a link to the new Next Generation Science Standards. We will be incorporating these standards in science courses next year. Although some revisions to units will be occurring over the summer, you should browse through the units of study posted on the right of the blog. I will be referring you to the blog frequently for review material, extra practice, homework assignments, and make-up work for students who are absent. It will be your responsibility in the upcoming year to check the blog at least weekly and sometimes more frequently.

Thursday, December 13, 2012

This is a link to an online Biology textbook.  It has videos and explanations of each topic.  You may want to use the appropriate sections to review.

Online Biology Book