Download The organization of animal and plant cells

Cell Biology
Concept 1: Common Features of All Cells
All cells, whether they are prokaryotic or eukaryotic, have some common
features.
The common features of prokaryotic and eukaryotic cells are:
1. DNA, the genetic material contained in one or more chromosomes and located in a
nonmembrane bound nucleoid region in prokaryotes and a membrane-bound nucleus in
eukaryotes
2. Plasma membrane, a phospholipid bilayer with proteins that separates the cell from
the surrounding environment and functions as a selective barrier for the import and
export of materials
3. Cytoplasm, the rest of the material of the cell within the plasma membrane,
excluding the nucleoid region or nucleus, that consists of a fluid portion called the
cytosol and the organelles and other particulates suspended in it
4. Ribosomes, the organelles on which protein synthesis takes place
Concept 2: Features of Prokaryotic Cells
Prokaryotes, which include all bacteria and archaea (archaebacteria), are the
simplest cellular organisms.
Prokaryotic cells are fundamentally different in their internal
organization from eukaryotic cells. Notably, prokaryotic cells lack a nucleus and
membranous organelles.
Concept 2 Practice: Identify the Features of Prokaryotic Cells
Label the components of a prokaryotic cell and explain the function of each. Enter name
of the structure and give its function.
1. Name: ______________________
Function:
2. Name: ______________________
Function:
3. Name: ______________________
Function:
4. Name: ______________________
Function:
5. Name: ______________________
Function:
6. Name:______________________
Function & Location:
7. Name: ______________________
Function & Location:
Review:
Concept 2 Review: Features of the Prokaryotic Cell
Prokaryotic cells have the following features:
1. The genetic material (DNA) is localized to a region called the nucleoid which has
no surrounding membrane.
2. The cell contains large numbers of ribosomes that are used for protein synthesis.
3. At the periphery of the cell is the plasma membrane. In some prokaryotes the
plasma membrane folds in to form structures called mesosomes, the function of
which is not clearly understood.
4. Outside the plasma membrane of most prokaryotes is a fairly rigid wall which
gives the organism its shape. The walls of bacteria consist of peptidoglycans.
Sometimes there is also an outer capsule. Note that the cell wall of prokaryotes
differs chemically from the eukaryotic cell wall of plant cells and of protists.
5. Some bacteria have flagella which are used for locomotion and/or pili, which may
be used to pull two cells in close contact, and perhaps to facilitate the transfer of
genetic material.
Concept 3: Features of Eukaryotic Cells
Eukaryotic cells contain a membrane-bound nucleus and numerous
membrane-enclosed organelles (e.g., mitochondria, lysosomes, Golgi
apparatus) not found in prokaryotes.
Prokaryotic cells are fundamentally different in their internal organization from
eukaryotic cells. Notably, prokaryotic cells lack a nucleus and membranous
organelles.
The nucleus is bounded by the nuclear envelope, a double membrane with many
nuclear pores through which material enters and leaves. Animals, plants, fungi, and
protists are all eukaryotes. Eukaryotic cells are more complex than prokaryotic cells
and are found in a great many different forms.
Concept 4: The Endomembrane System in Eukaryotic Cells
All eukaryotic cells have within them a functionally interrelated membrane
system, the endomembrane system consisting of the nuclear envelope, ER and
Golgi apparatus, vesicles and other organelles derived from them, and the
plasma membrane.
Many materials are moved around the cell by the endomembrane system, including
some proteins.
A typical animal cell:
There are many different types of cells. One major
difference in cells occurs between plant cells and animal cells. While both plant and
animal cells contain the structures discussed above, plant cells have some additional
specialized structures. Many animals have skeletons to give their body structure and
support. Plants do not have a skeleton for support and yet plants don't just flop over in a
big spongy mess. This is because of a unique cellular structure called the cell wall. The
cell wall is a rigid structure outside of the cell membrane composed mainly of the
polysaccharide cellulose. As pictured at left, the cell wall gives the plant cell a defined
shape which helps support individual parts of plants. In addition to the cell wall, plant
cells contain an organelle called the chloroplast. The chloroplast allow plants to
harvest energy from sunlight. Specialized pigments in the chloroplast (including the
common green pigment chlorophyll) absorb sunlight and use this energy to complete
the chemical reaction:
6 CO2 + 6 H2O + energy (from sunlight) C6H12O6 + 6 O2
In this way, plant cells manufacture glucose and other carbohydrates that they can store
for later use.
Organisms contain many different types of cells that perform many different functions.
The following link is a great site to learn more about cells and cell structure.
This would be an ideal site to use during our unit of study on the cell and especially as you
work on your cell model project.
Try it out and let me know what you think.
http://www.biology4kids.com/files/cell_main.html
This next site links you directly to the textbook which we use in class. What you find here is
an "interactive" site that will reinforce or help clarify all that we cover in class. You will also
find practice tests to help you learn the information and better prepare you to be successful
in this course. I encourage all of you to use this site frequently. There are links to other
sites that will help you understand the concepts and to see ideas / facts presented in
different ways. This will help reinforce the learning process. Good luck!
http://www.phschool.com/atschool/science_explorer/CellsHeredity/Student_Area/SE_C_SC1_A
CT_index.html
Be sure to visit the next site, Cells Alive. Start by clicking on Cell Biology. There is also an
excellent "Plant and Animal Cell Models" section that can be helpful with your Cell Model
project. Be sure to take the "quiz" when you've completed viewing the site contents.
http://www.cellsalive.com/
The next site lets you explore the structure of a virtual plant cell. You can zoom in on
organelles, cut or turn them, look at real EM (electron micrograph) images and more. Check it
out!
http://www.life.uiuc.edu/plantbio/cell/
The following site links you to the Access Excellence Graphics Gallery and a diagram of "The
Cell." Look up a description of "Cell" in the NHGRI Talking Glossary's link.
http://www.accessexcellence.org/AB/GG/cell.html
The organization of animal and plant cells
Red color indicates the difference between them.
The eukaryotic cell contains organelles, which are defined as membrane-bound
structures such as nucleus, mitochondria, chloroplasts, endoplasmic reticulum (ER),
Golgi apparatus, lysosomes, vacuoles.
For animal cells, the cell surface consists of the plasma membrane only, but plant cells
have an additional layer called cell wall, which is made up of cellulose and other
polymers
Scanning Electron Microscope (SEM)
The JavaScript SEM for Students
----These pages use JavaScript to create the illusion of controlling a Scanning Electron
Microscope (SEM). You must be using Netscape 3.0 or higher and JavaScript must be
enabled.
Click on the following link to begin using the Scanning Electron Microscope
(SEM):
http://search.netscape.com/ns/boomframe.jsp?query=http%3A%2F%2Fwww.de
nniskunkel.com&page=1&offset=0&result_url=redir%3Fsrc%3Dwebsearch%26req
uestId%3Df6332de31fe63201%26clickedItemRank%3D3%26userQuery%3Dhttp
%253A%252F%252Fwww.denniskunkel.com%26clickedItemURN%3Dhttp%253A%
252F%252Feducation.denniskunkel.com%252F%26invocationType%3D%26fromPage%3DNSCPResults%26amp%3BampTest%3D1&remove_url=http%3A
%2F%2Feducation.denniskunkel.com%2F