5th Period's Cell


*DO NOT add information to this page until this evening. NO ONE should edit this page in class.

1) Your class is going to create a cell.

2) Each of you have been assigned a particular part of a eukaryotic cell.

3) Research and collect information regarding the following:
-what your part looks like
-what it does for the cell
-the size of your part
-pictures and links to websites about your cell part

4) DO NOT add your information to this page until this evening. NO ONE should edit this page in class.

Homework: Insert the information you collected regarding your organelle onto this webpage. I will be checking your work tonight and grading you on the quality of the information you have provided your classmates.

This is also a class competition! May the best cell win!

Will - Cilia
KT - Flagellum
Ara - Plasma membrane
Sally - Cytoskeleton
Lauren - Endoplasmic reticulum
Andy - Nucleus
Steph - DNA
Danny - Nucleolus
Hank - Vacuole
Amanda - Lysosome
Taylor - Ribosomes
Steven - Mitochondria
Grant - Golgi apparatus
Bryant - Vesicles
Jennifer - Chloroplast

The Cilia

Cilia are projections of the cell.

In mammalian cells, the cilia moves fluid, mucous, or cells over their surface. Cilia can actually move the cell.

Cilia and flagella have the same internal structure, the only difference is their length.

Cilia are made up of microtubules, which are kind of like conveyer belts inside the cell.
Here is a diagram that shows where the cilia are.
*Cilium is the singular form of cilia.
cilia1.jpg cilia4.jpg
The diagram above shows how the microtubules are arranged in the cell. Collectively, the microtubules are called an “axoneme”. The diagram shows what a microtubule looks like on the surface and a view of the inside of it. If two, microtubules join together, it becomes a ciliary doublet. In the same way, if three come together, it becomes a centriolar triplet.
The picture above is a cross view of a cilium. Notice how there is nine doublets in a ring that have a part of an incomplete microtubule on them. Extending off the doublets is an arm made out of the protein dynein and join neighboring doublets together. In the center of the ring are two complete microtubules.

These are two micrographs of some cilia.

Source for the diagrams and lines above.

The size of vacuoles may vary in different tissues and stages of development.
They preform functions for the cell sauch as storage, ingestion, digestion, excretion, and expulsion of excess water.
external image plantcell.gifexternal image vacuole.jpeg
Nuber 2 on this picture is the vacuole.
Here is a great link!
hi.png 10_small_subunit.gif
The ribosomes’ function is to assemble proteins. That process is called translation. They translate by speeding up the assembly of amino acids into a polypeptide chain.

Ribosomes are generally very small. They are 20nm in diameter.They are made up of 50 proteins and several RNA strands (which is a nucleic acid) bound together.

Golgi Apparatus


*Unfortunately I can not get these images to show up but here are the links.
Golgi Apparatus 1
Up-Close of Golgi Apparatus

The Golgi Apparatus, also known as the Golgi body or Golgi complex, is a series of mebranous vecesicles that are stacked on each other and are in most live cells. It functions during the formation, in the cell, of secretions. It can be found in both plant and animal cells. They are normally made up of a series of five to eight cup-shaped, membrane-covered sacs, known as cisternae, that are similar in appearance to a pile of deflated balloons. In some flagellates, up to 60 cisternae can combine to form the Golgi Apparatus. The amount of Golgi bodies in a particular cell vary based on its function. Animal cells normally contain around ten to twenty Golgi stacks that have been linked into a single complex by tubular connections between the individual cisternae. The previously mentioned complex is close in location to the cell nucleus. The Golgi Apparatus is relatively large which contributed to it being one of the first organelles that was ever observed. It is normally know as the shipping and distribution center for the chemical products of the cell. It changes proteins and lipids that were built while in the endoplasmic reticulum. It does this to make them ready to be exported out of the cell or to be transfered to other parts of the cell. The proteins and lipids then break off into vesicles and move through the cytoplasm until they reach their destination, the Golgi Complex. After their arrival at their destination, these vesicles, that resemble bubbles, fuse into the Golgi membranes where they let go of their molecules, that are stored internally, into the molecules. After the molecules have been released into the molecules, they are processed even more by the Golgi apparatus. It now adds molecules or cuts of small pieces at each end. When this process has been completed, the final product is extruded from the Golgi apparatus where it then heads to the outside of the cell. This final product is a secretion of proteins or glycoproteins that are a part of the function of the cell in an organism. The products that don’t go outside of the cell return to the endoplasmic reticulum or could undergo maturation and become lysosomes. The Golgi apparatus is located near the endoplasmic reticulum and the nucleus. It consists of three parts:
1) Cis Golgi Network
This is place of entrance into the Golgi apparatus.
2) Golgi Stack
This consists of the cisternae which are divided into three areas for working: the cis cisternae, medical cisternae, and the trans cisternae.
3) Trans Golgi Network
This part of the Golgi is connected directly to the tans cisternae of the Golgi stack and is the part of the Golgi where the final sorting and reactions take place. The biochemicals are packed into vesicles and break off from the surface of the trans Golgi. They are then transported for use in the cell and other places.

Source 1
Source 2
Source 3
Source 4

Diagram of this Process

The flagella, or cilia, are microscopic hair like structures projecting from the cell. They are a minor organelle used to generate motion. They contain cytoplasm and are located inside the plasma membrane.

The Eukaryotic flagellum is made up of a bundle of nine fused pairs of microtubule doublets surrounding two central single microtubules. . At the base of a eukaryotic flagellum is a "basal body" which is the microtubule
organizing center for flagella microtubules and is about 500 nanometers long.


What it does for the cell
Lysosomes digest macromolecules such as monosaccharides and break down damaged or old parts as well as bacteria.
Lysosomes are tiny organelles. Each is surrounded by its own membrane due to the acidic conditions within it. The membrane protects the digestive enzymes inside from destroying the cell. Lysosomes use hydrolytic enzymes to break down substances.

external image lysosomesfigure1.jpg

How big is it
Lysosomes are very tiny, microscopic organelles.

What it looks like

external image gaucher.gif

plasma memebrane
it looks like
Plasma Membrane Structure
Plasma Membrane Structure

All living cells, prokaryotic and eukaryotic, have a plasma membrane that encloses their contents and serves as a semi-porous barrier to the outside environment. The membrane acts as a boundary, holding the cell constituents together and keeping other substances from entering.



The (Smooth) Endoplasmic Reticulum







What it does…
I found what a Smooth Endoplasmic Reticulum (SER) was here is the information that I found on that one site about the SER.
The smooth endoplasmic reticulum (SER), found in eukaryotic cells, is a system of membrane-enclosed tubes within the cytoplasm of a cell. It is a transport system for the cell, but it also makes lipids, processes carbohydrates, and detoxifies substances, such as poisons and alcohol. The specific function of the SER depends on the cell. For example, in liver cells, the SER detoxifies substances. In cells of the adrenal glands and gonads, cholesterol is modified in the SER at one stage of its conversion to steroid hormones. And in muscle cells, the SER withdraws calcium ions from the cytoplasm. The amount of SER varies with each cell also. The cells in the oil glands of the skin have a large amount of SER because the SER produced lipids. The SER also divides the cytoplasm of the cell into compartments

(Website: http://sun.menloschool.org/~birchler/cells/animals/smooth_er/ )

http://biology.about.com/library/weekly/aa041300a.htm -look at this site


Eukaryotic cells are usually much larger and more complex than prokaryotic cells. Because of their larger size, they require a many more specialized internal membrane-bound organelles to create a metabolism, make energy, and carry chemicals all through the cell. The nucleus is the basis of a cell; it contains the DNA of the cell, directs cellular reproduction, and regulates the cell’s metabolism rate.


DNA is the hereditary material in humans and almost all other organisms. Most of the DNA in a cell is found near the nucleus, but it can also be found in the mitochondria. Information in DNA is stored as a code made up of only four chemical bases. They are adenine (A), guanine (G), cytosine (C), and thymine (T). These bases pair up with each other to form base pairs. A pairs with T and C pairs with G. Each of these bases is attached to a sugar and phosphate molecule which forms a nucleotide. Nucleotides arrange themselves in two strands to form a double helix. DNA can replicate so that when cells divide, both cells have the exact same strands of DNA in them.

This picture shows the location of DNA and how small it is within the cell.


this is a good link for a video that says a little bit about the cell and DNA. It shows just how small this DNA really is.

this is really dumb, a picture of plastic DNA, but it gives you a good idea of its size

Vesicles are like the taxi-cabs of the Golgi complex and the Endoplasmic Reticulum. They transport molecules, proteins specifically, to the Golgi complex, and from the Golgi complex to other areas of the cell. Still, they can carry other things to other parts of the cell, like Lysosomes for example. Lysosomes are a type of vesicle, and they're used to carry enzymes to help digest food in the cell.

How and WHY?!?
Well, first of all, in the Eukaryotic cell, many proteins must be synthesized, or basically made. SO, this job is left to something called the Endoplasmic Reticulum (ER). After the ER makes the proteins, they’re just sitting there, sloppily thrown together. It’s like walking into a grocery store, and instead of the bread being sliced and in a bag, there’s just a loaves of bread thrown and crushed one on top of another, stuffed into the shelves, with the plastic bags thrown everywhere in between the loaves, with the twist tie sticking out of the tops of the loaves of bread. Now, the proteins have to be packaged properly and in some cases modified (almost like slicing the bread before it’s bought and used). However, it can’t do that, it’s too busy making proteins. Next to that, it’s already done its job. Also, that might take too much energy for something so big and important to do that much work. So, why not get someone else to do it? This job is left to the ever hard-working Golgi Complex. The Golgi complex just modifies and sorts out the different proteins it receives.
However! There’s no way for the Golgi complex to get the proteins, and what not.
VESICLES to the rescue! Vesicles transport these molecules by trapping them in a sort of bubble. This bubble is made up of basically membranes. Once the proteins, or item that needs to be transported, is trapped inside the vesicle, it’s taken to its needed location. Check out these pictures to actually see what they look like.

Notice how in some, it’s almost like they are (the vesicles) just dots next to the Golgi complex. This is because when they get to the Golgi Complex, they just become apart of it, and then the protein is released into the Golgi. It’s almost like they fuse with the Golgi. Then, when the protein has been all fixed up, and ready to go, it moves to the other end of the Golgi. Then, that part of the Golgi that contains the eager proteins breaks off at the end. Now, you’ve got a whole new vesicle! That’s why the vesicles might look small dots around the sides of the Golgi Complex. Same concept goes for the ER, as seen in this picture.
Sorry the pictures are so tiny, but when I try to enlarge them, it gets blurry. Just go to the websites I got it from, although, I must warn you, the text is written on a kind of high level.

Here are some other websites I thought were pretty good in explaining the function of vesicles.
· http://www.cytochemistry.net/Cell-biology/lysosome_sorting.htm
· http://biology.clc.uc.edu/courses/bio104/cells.htm
· http://www.primordion.com/pub/mscCoursework/NetLogo_InformationSection.pdf hint: It’s a lab, but the beginning gives a good explanation of how the Golgi Complex, ER and Vesicles are all related.
· http://www.scienceclarified.com/Ca-Ch/Cell.html this is a good one also
Again, on some of these websites, the text can get a little confusing, but they get the main point across.

Cytoskeleton is the "skeleton" or the "framework" of the cell in the cytoplasm. They consist of protein molecules combined into chains.
It is present in all cells, and is a dynamic structure that maintains cell shape. It is also known to protect the cell, enables cellular motion (using the flagella, cilia and lamellipodia), and plays important roles in both intracellular transport (the movement of vesicles and organelles, for example) and cellular division. Click here to see an article that has more elaborate facts on cytoskeletons.