Module 2 Overview The Cell and Energy Every tissue in every body of every organism is made of cells.  The complexity of life ranges from the single-celled amoeba to large mammals containing innumerable cells, with many distinct types performing specific functions.  This module will introduce you to the structure and function of cells and will describe the two major types—prokaryotic and eukaryotic cells.  You will then be introduced to the various types and functions of specific protein molecules called enzymes, which facilitate cellular processes. All organisms require energy to perform the functions that sustain their lives.  The chemical reactions at the heart of these functions are referred to as an organism's metabolism.  The biochemical or metabolic pathways that these reactions take are a series of linked reactions that transform energy into a usable form. Learning Objectives Upon completion of this module, you should be able to: 2A Identify the typical organelles associated with eukaryotic cells. 2B Examine the differences in organelles found in prokaryotic and eukaryotic cells. 2C Describe the function of each of the organelles associated with eukaryotic cells. 2D Name examples of organisms composed of prokaryotic and eukaryotic cells. 3A State the controlled methods by which materials can be transported through a cell membrane. 3B Contrast diffusion, osmosis, and dialysis. 3C Classify the components and molecular parts of a typical cell membrane. 3D Explain why cells are small. 3E State what environmental factors are able to alter enzyme activity. 3F Describe to which group of organic molecules enzymes belong. 3G Explain why enzymes are so important to all organisms. 3H Describe what happens when an enzyme and a substrate combine. 3I Contrast active site and binding site. 3J Define the term, denature, and provide negative and positive feedback. 3K Describe enzymatic competition. 3L Relate the shape of an enzyme to its ability to help in chemical reaction. 3M Describe why enzymes work in some situations and not in others. 3N Contrast cofactors, vitamins, and coenzymes. 3O Explain the importance of ATP. 3P Describe how the proton pump mechanism generates ATP. Module 2 Reading Assignment Enger, E. D., Ross, F. C., & Bailey, D. B. (2012).  Concepts in biology (14th ed.). New York: McGraw-Hill. Chapters 4 and 5. Lecture Notes The Cell and Energy Prokaryotic cells are smaller than eukaryotic cells.  While eukaryotic cells can be much larger, they are still small.  Cell size is important for a couple different reasons.  Logistically, small cells are easier to replace.  This is why they replicate and split.  When cells become too large, it is more beneficial to split off and remain small and effective than to become too large, become less effective, and become harder to replace.  The effectiveness of absorption and expulsion through the plasma membrane is another reason why cells are small.  Absorption and expulsion beco ...

1. Module 2 Overview
The Cell and Energy
Every tissue in every body of every organism is made of cells.
The complexity of life ranges from the single-celled amoeba to
large mammals containing innumerable cells, with many distinct
types performing specific functions. This module will introduce
you to the structure and function of cells and will describe the
two major types—prokaryotic and eukaryotic cells. You will
then be introduced to the various types and functions of specific
protein molecules called enzymes, which facilitate cellular
processes.
All organisms require energy to perform the functions that
sustain their lives. The chemical reactions at the heart of these
functions are referred to as an organism's metabolism. The
biochemical or metabolic pathways that these reactions take are
a series of linked reactions that transform energy into a usable
form.
Learning Objectives
Upon completion of this module, you should be able to:
2A
Identify the typical organelles associated with eukaryotic cells.
2B
Examine the differences in organelles found in prokaryotic and
eukaryotic cells.
2C
Describe the function of each of the organelles associated with
eukaryotic cells.
2D
Name examples of organisms composed of prokaryotic and
eukaryotic cells.

2. 3A
State the controlled methods by which materials can be
transported through a cell membrane.
3B
Contrast diffusion, osmosis, and dialysis.
3C
Classify the components and molecular parts of a typical cell
membrane.
3D
Explain why cells are small.
3E
State what environmental factors are able to alter enzyme
activity.
3F
Describe to which group of organic molecules enzymes belong.
3G
Explain why enzymes are so important to all organisms.
3H
Describe what happens when an enzyme and a substrate
combine.
3I
Contrast active site and binding site.
3J
Define the term, denature, and provide negative and positive
feedback.
3K

3. Describe enzymatic competition.
3L
Relate the shape of an enzyme to its ability to help in chemical
reaction.
3M
Describe why enzymes work in some situations and not in
others.
3N
Contrast cofactors, vitamins, and coenzymes.
3O
Explain the importance of ATP.
3P
Describe how the proton pump mechanism generates ATP.
Module 2 Reading Assignment
Enger, E. D., Ross, F. C., & Bailey, D. B. (2012). Concepts in
biology (14th ed.). New York: McGraw-Hill. Chapters 4 and 5.
Lecture Notes
The Cell and Energy
Prokaryotic cells are smaller than eukaryotic cells. While
eukaryotic cells can be much larger, they are still small. Cell
size is important for a couple different reasons. Logistically,
small cells are easier to replace. This is why they replicate and
split. When cells become too large, it is more beneficial to split
off and remain small and effective than to become too large,
become less effective, and become harder to replace. The
effectiveness of absorption and expulsion through the plasma
membrane is another reason why cells are small. Absorption
and expulsion become more difficult as cell size increases.
In more recent history, scientists have discovered that there are
different types of cells and different functions, but that the

4. basic cell theory still holds true. Cell theory is one of biology’s
basic principles. Living organisms must be made up of cells
whether they are unicellular or multi-cellular. All cells come
from already existing cells and have the same basic
configuration. Cells are a basic unit of life that allow energy to
flow and hereditary information to be replicated and passed on.
Diffusion occurs within liquids and gases when there are no
barriers. Basically, molecules will diffuse into spaces that are
less concentrated than their current environments in an attempt
to equalize; therefore, molecules are always in motion.
Osmosis is passive in its transport of molecules. Molecules
follow the direction of the flow of liquid or gas, rather than
trying to equal out the concentration. Osmosis occurs each time
there is a selectively permeable membrane with varying
concentrations on each side of that membrane. Please watch
the Cell Membrane Passive Transport video to learn more about
the cell membrane, passive transport, and cell biology:
There are a few basic differences in organelles that are found in
prokaryotic and eukaryotic cells. Prokaryotic cells are
generally smaller cells that are anatomically simple. There is
an absence of a nucleus and most other organelles. Prokaryotic
cells are bacteria. Eukaryotic cells are usually much larger than
prokaryotic cells and are also more intricate. They have a
nucleus as well as an assortment of organelles. Eukaryotic cells
make up plants, animals, fungi, protozoa, and algae.
Enzymes are vital to all living things because they are the
foundations of energy, and energy is needed to survive—even at
the cellular level. Enzymes are responsible for controlling and
speeding up most biochemical reactions. They are discerning to
what reactions are sped up so as not to set off unwanted
reactions. Enzymes and the production of energy are important
in everything from digestion to reproduction.
A binding site is indiscriminative, which allows an enzyme to
attach anywhere there is a binding site. Binding sites do not
allow production, however. An active site is discriminative to
enzymes because the active site is where the biochemical

5. reaction occurs. In order for any reaction to occur, there needs
to be activation energy. Activation energy makes things a bit
unstable allowing for the enzyme to start a reaction. Therefore,
an enzyme must first attach to an active site and then receive
some activation energy in order for a reaction to occur.
Cofactors, vitamins, and coenzymes are intertwined in helping
enzymes with their reactions. The major difference in cofactors
and coenzymes is that cofactors are inorganic molecules and
coenzymes are organic molecules. Cofactors help with
biochemical reactions by increasing the rate of the catalysis
while coenzymes are essential for some enzymes to carry out
reactions. For some enzymes, they are unable to make a
reaction until they pair up with another protein, making them a
coenzyme. Vitamins, like coenzymes, are organic. Vitamins
help to produce coenzymes and are vital for cellular functions.
However, by themselves, they do not have any energy, which is
why they need to pair with an enzyme.
There are a few environmental factors that can alter enzyme
activity. The first is temperature. Temperature is able to
change the rate of motion and in some cases, the shape of the
enzyme. The rate of motion slows with both high and low
temperatures. Change in the shape of an enzyme occurs when
there is continually high temperature. Once the enzyme changes
shape, it is damaged and will not go back to its original shape.
pH is another environmental factor that can change the enzyme
activity. With pH, the enzyme shape can be changed when
hydrogen ions attach. Lastly, enzyme-substrate concentration
can change enzyme activity. If there is too much substrate, the
rate is unable to increase unless more enzymes are provided.
ATP, or adenosine triphosphate, is important because it allows
energy to be released in a way that does not damage the cell. It
releases only the amount of energy that the cells need. ATP is
made up of three phosphate groups. These groups hold the
energy until the cell needs it. When the cell needs the energy,
it breaks off one of the phosphate groups and becomes ADP, or
adenosine diphosphate. Breaking down to ADP ensures that the

6. cell will not receive too much energy.
Required Presentations:
Click on the links below to view the Module 2
presentations.Chapter 4Chapter 5
[INSERT TITLE HERE] 1
Running head: [INSERT TITLE HERE]
[INSERT TITLE HERE]
Student Name
Allied American University
Author Note
This paper was prepared for [INSERT COURSE NAME],
[INSERT COURSE ASSIGNMENT] taught by [INSERT
INSTRUCTOR’S NAME].
PART I: SHORT ANSWER

7. Directions: Please answer each of the following questions.
Please ensure that your responses are at least 3 to 5 sentences in
length.
1. Describe how the concept of the cell has changed over the
past 200 years.
2. On the basis of surface area-to-volume ratio, why do cells
tend to remain small?
3. List the membranous organelles of a eukaryotic cell, and
describe the function of each.
4. What will happen if an animal is placed in a hypertonic
solution?
5. Describe three of the six methods that allow the exchange
of molecules between cells and their surroundings.
6. What is the difference between a catalyst and an enzyme?
7. Describe the sequence of events in an enzyme-controlled
reaction.
8. How do these three types of molecules relate to one
another (enzymes, coenzymes, and vitamins)?
9. Describe what happens during electron transport and what
this has to do with a protein pump.
10. What is enzyme competition and why is it important to all
cells?
PART II: ESSAY
Directions: Write a 1 to 2 page, double-spaced paper in 12 pt.

8. font in response to the following question. Find one article
using AAU’s LIRN (library) to use as support. Please use APA
format. Please visit the Academic Resource Center for an
effective guide on how use LIRN and for concise APA
guidelines.
Prokaryotic and Eukaryotic Cells
Compare and contrast the differences between prokaryotic and
eukaryotic cells. Explain what organisms have prokaryotic and
eukaryotic cells, what makes each of these cells unique, and
why they are very important in our environment.