MANGUBAT, REYNALD O.
BSN -1B
Activity: By pair, answer the following questions:
1. What are enzymes?
Enzymes are biological molecules, typically proteins, that act as
catalysts to speed up chemical reactions in living organisms. They are not
consumed in the reactions they catalyze and can be used repeatedly.
2. What are the functions of an enzyme?
Enzymes have specific functions in the body, such as aiding in digestion,
DNA replication, and hormone production.
3. How are enzymes named and classified?
They are named and classified based on the reactions they catalyze. The six
broad groups of enzymes include hydrolases, oxidoreductases, lyases,
transferases, ligases, and isomerase. The names of enzymes typically end in "-
ase," and their classification is based on the type of reaction they catalyze.
4. Define the following:
a. Coenzyme - A non-protein molecule that binds to an enzyme and is
essential for its function. Coenzymes are often vitamins or prosthetic
groups.
b. Apoenzyme - The protein part of an enzyme without any coenzymes
or ligands attached to it.
c. Substrate - The molecule that binds to the active site of an enzyme
and undergoes a change in a chemical reaction.
d. Active site - The specific location on an enzyme where the substrate
binds, and the enzyme-catalyzed reaction occurs.
e. Competitive inhibitors - Molecules that bind to the active site of an
enzyme and prevent the substrate from binding to it. They "compete"
with the substrate for the active site, and their presence increases the
Km of the enzyme.
f. Non-competitive inhibitors - Molecules that bind to a site distinct
from the active site and prevent the enzyme-catalyzed reaction from
occurring. They do not compete with the substrate for the active site
and are not affected by changes in substrate concentration.
5. What are the factors that affect enzyme activity? Explain each.
Factors Affecting Enzyme Activity:
Temperature: Enzyme activity increases with temperature, but at high
temperatures, the enzyme can denature and lose its function.
pH: Enzymes have an optimal pH at which they function best. Deviation from
this pH can denature the enzyme and affect its activity.
Enzyme Concentration: An increase in enzyme concentration generally leads
to an increase in the rate of reaction, provided the substrate is not a limiting factor.
Substrate Concentration: Initially, an increase in substrate concentration
leads to an increase in the rate of reaction. However, after reaching a certain point, the
enzyme becomes saturated, and the rate of reaction levels off.
Inhibitors or Activators: Molecules that can inhibit or activate enzyme activity.
Competitive inhibitors compete with the substrate for the active site, while non-
competitive inhibitors bind to a different site, altering the enzyme's shape and activity.
6. How do cells regulate the production of enzymes and why is it necessary
to regulate the production of enzymes?
Cells regulate the production of enzymes through a process called enzyme
regulation . Enzyme regulation is the process by which cells control the
activity of enzymes, which are essential for many cellular processes . Enzymes
are regulated to ensure that they are produced in the right amounts and at the
right time . This is necessary because different cells have different needs and
conditions, and the amounts and functionality of different enzymes change
over time .
