http://www.scilinks.org
Topic: Enzyme Activity
Keyword: HX407142 CHAPTER 2Chemistry of Life
Analysis- Name the enzyme that
works best in highly acidic
environments. - Name the enzyme that
works best in less-acidic
environments.
3.Critical Thinking
Analyzing DataIdentify the
pH value at which trypsin
works best.
4.Critical Thinking
Analyzing DataIdentify
the pH value at which pepsin
works best.5.Critical Thinking
Inferring Relationships
What does the graph indicate
about the relative acidity of the
stomach and small intestine?Analyzing the Effect of
pH on Enzyme Activity
Background
The graph at right shows the relationship between
pH and the activity of two digestive enzymes,
pepsin and trypsin. Pepsin works in the stomach,
while trypsin works in the small intestine. Use the
graph to answer the following questions.0100010110
011101010
0010010001001
1100100100010
0000101001001
1101010100100
0101010010010
12PepsinTrypsin3456789Rate of reactionpHEnzymes and pHListthree ways that organisms use energy. 12ASummarizehow energy is made available by
chemical reactions. 4BExplainhow enzymes increase the speed of
chemical reactions. 9CDescribehow the enzyme amylase affects starch.Critical Thinking Predicting OutcomesWhat
effect might a molecule that interferes with the
action of carbonic anhydrase have on your body?Carboxypeptidase is an enzyme
that catalyzes reactions in the small intestine. The
products of these reactions are amino acids. What
are the substrates of carboxypeptidase? 9C
Aproteins Clipids
Bcarbohydrates Dnucleic acidsTAKS Test PrepTAKS Test PrepSection 4 Review
Factors in Enzyme Activity
Any factor that changes the shape of an enzyme can affect the
enzyme’s activity. For example, enzymes operate most efficiently
within a certain range of temperatures. Temperatures outside this
range can either break or strengthen some of the enzyme’s bonds,
changing its shape. Moreover, each enzyme operates best within a
certain range of pH values. A pH value outside this range can cause
bonds in an enzyme to break, reducing the enzyme’s effectiveness.
The enzymes that are active at any one time in a cell determine what
happens in that cell. Your body’s cells contain many different enzymes,
and each enzyme catalyzes a different chemical reaction. Different
kinds of cells contain different collections of enzymes. For example, as
you read this page, the chemical reactions occurring in nerve cells in
your eye are different from the chemical reactions occurring in your
red blood cells.9C9D2C 9C