Science Thinker

Virtual lab links to make up missed labs.

To make up “Rate of Diffusion” lab. Go to the following link, follow directions for recording data, answer the questions in full sentences, and put in my drop box.

Link: http://biologyonline.us/Online%20A&P/AP%201/Northland/AP1lab/Lab%20Online/Virtual%20Labs/Transport%20Index.htm Do only the lab for Diffusion rate. Another link to help with concept: http://highered.mcgraw-hill.com/sites/007352543x/student_view0/chapter5/how_diffusion_works.html

Link to make up missing “The effects of temperature on Enzyme Activity”.

Link: http://www.mhhe.com/biosci/genbio/virtual_labs/BL_11/BL_11.html

It deals with the effects of various pH on enzyme activity.

Data Table: Rate of Product formation

Amount of Substrate	pH3	pH5	pH7
0.5g
1.0g
2.0g
4.0g
8.0g

 

Questions:

1. Describe the relationship between substrate concentration and the initial reaction rate of an enzyme-catalyzed reaction. Is this a linear relationship? What happens to the initial reaction rate as substrate concentration increases? (Plot your data on a line graph, then answer the questions)

 

 

 

 

1. What is the maximum initial reaction rate for this enzyme at pH 7?

 

 

 

 

1. Explain why the maximum initial reaction rate cannot be reached at low substrate concentrations.

 

 

 

 

1. What does your data indicate about the optimum pH level for this enzyme-catalyzed reaction?

 

 

1. Enzymes function most efficiently at the temperature of a typical cell, which is 37 degrees Celsius. Increases or decreases in temperature can significantly lower the reaction rate. What does this suggest about the importance of temperature-regulating mechanisms in organisms? Explain.