Monday, September 22, 2014

Instructions for 9-22-14 Cell Transport Activity

Follow the instructions on your handout and use the following links.  Click on the link to visit it.

SODIUM-POTASSIUM PUMP - AN EXAMPLE OF ACTIVE TRANSPORT

FACILITATED DIFFUSION ANIMATION

SIMPLE DIFFUSION ANIMATION

1.  Draw each type of animation in your notebook and label it.  Make sure to include all 3:   Simple diffusion, facilitated diffusion, and active transport, and make sure to label each.

2.  Describe the characteristics of each type of transport for the following topics:

-Direction of movement (down the concentration gradient from more to less OR up the concentration gradient from less to more)

-Does it require a protein channel or not

-Types of molecules that would use it - based on size and polarity  (Example:  small, nonpolar molecules would use this type of transport).

-Does it require energy expenditure by the cell or not?

3.  Answer Question 4 from Friday's activity.

Thursday, September 18, 2014

Advanced Practice for Diffusion and Osmosis

Go to the PHS LabBench Activity, complete the exercises, and the questions provided.  Record answers in your notebook as you complete the activity.

http://www.phschool.com/science/biology_place/labbench/lab1/intro.html

Monday, September 15, 2014

Extra Practice for Cell Membranes and Transport Predictions

How to predict if a molecule is polar

Membranes

Practice Problems with Answers

If you wish to retake the assessment, read and gain an understanding from the first two links.  Use this understanding to attempt the practice problems.  Check your answers to see if you are correct.

Write an explanation for each answer.  Tell why it is correct.  You should have logical reasoning for each answer and be able to explain it to me when you come in to retake the assessment.  The answer key is provided to help you confirm whether or not you are correct.  Writing down the answers without doing the problems will not earn you the opportunity to retake the assessment.

After you have completed the work, bring it to me.  We will go over it, and you will be provided with a new assessment to help you improve your score.

All assessment retakes must be completed prior to Friday September  26, 2014.  Also, I will not be at school on the 25th due to a professional development training.

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