Cell Lab

Introduction:


The fundamental structure of all life is the cell. In this lab the goal is to produce an accurate representation of a cell and its working organelles, and processes. One of the fundamental characteristics of any living thing is the ability to replicate itself. So the model will also have to show the process for replication. For my model I decided to use items which could represent the organelles of a cell as well as building miniature representations of some of the organelles and parts. Using some imagination and photos from the PowerPoint and text book I assembled a cell model with both creativity and simple representation of a complex world.


Cell parts:
Cytoskeleton = yellow playground ball and paperclips for upper frame
Plasma membrane with bi layer lipids= blue tinted cellophane
Cell plasma = blue foam
Protein embedded in lipids for plasma membrane = one cut section of red rubber pencil grip
Nuclear envelope = tennis ball shell
Nucleus = plastic golf ball shell
DNA wrapped in chromatin = green/purple rubber pencil grips
mRNA = yellow rubber pencil grip
Ribosome’s = small spherical metal pieces
Rough endoplasmic reticulum = small wood logs with spiraling grooves
Smooth endoplasmic reticulum = small smooth round wooden balls
Protein being synthesized = 15amp fuses
Golgi apparatus = small wooden factory
Mitochondria = battery
Lysosomes = thumb monster with no hands
Vesicle = sowing thimble
ATP (adenosine triphosphate) = pencil eraser tips





In my first picture you have the front view of my completed cell model. Its my hope that a person familiar with the structure of a cell can see this one photo and recognize the concepts I was trying to reproduce. In this photo the cell membrane is very easy to identify as a selectively permeable layer, which separates the cells internal structure from the outside environment allowing the cell to be homeostasis. I also hope that even someone who is not familiar with a cell structure could see this picture and start to visualize what the different components could be representing.

In this photo I have some of the various tools and the majority of items I used to start the process of building a cell. Many of these items you will see in upcoming photos where there application will make more sense. One other thing to point out, for my model I started with certain ideas of what my cell would look like, and with any good creator of something the ideas evolved and many items were added to making the cell which are not shown in the picture.

This photo shows the basic structure my cell will be taking. For the cytoplasm, cytoskeleton and cell membrane I wanted a spherical look as well as a 3 dimensional representation. The rubber ball was perfect to use for showing circular uniformity. The ball shell represents the cytoskeleton which gives the cell its form and also keeps the organelles in a particular location within the cell. The blue foam acts as a medium for the rest of the organelles and represents the cell plasma generally made of water as the universal salute.

In this photo you can see the basic components for building the upper portion of the cytoskeleton and the framework for my visual aid of the cell membrane.

I used a soldering gun and paper clips to build a three leg frame with a triangle base. The triangle platform will have a protein representation on top to help explain how the cell membrane is permeable.

Here is the completed cytoskeleton with a triangle platform on top.

This is the most complicated photo in the sense there are multiple organelles and process taking place in this one picture. Starting with the nuclear envelope shown here as the outer circular shape (tennis ball shell) which house's the actual nucleus and DNA. The nucleus is shown as a white sphere (plastic golf ball shell). Inside the nucleus is the DNA (finger cushions for pencils). The DNA is shown already wrapped in protective proteins called chromatin (purple and green), but you can see the DNA symmetry representing the double helix structure (this will be explained in the next photo). Along with the DNA is the the messenger mRNA which transfers the genetic code from the nucleus outside of the nuclear envelope to the ribosome’s for protein synthesis. The messenger mRNA is shown as a strand of yellow mRNA transferring the genetic information to the ribosome’s were amino acids join with the mRNA and start to fold into the specific protien, this entire process is called "gene expression". The ribosome’s are shown as small spherical metal disks which are connected to the rough endoplasmic reticulum. I used small wooden logs with spherical groves wrapping around to show rough endoplasmic reticulum where the proteins are made. The proteins job is to cause specific catalyzing chemical reactions as one of thousands of reactions needed for the cells metabolism. Here you can see the proteins (blue 15 amp fuses) being made. Next to the rough endoplasmic reticulum is the smooth endoplasmic reticulum (small wooden spheres) which produces carbohydrates (long term energy for the cell) and lipids (used in the cell membrane).

This photo represents cell mitosis, cell mitosis is the splitting of a cell into two identical sister cells. During cell mitosis there are four phases the cell undergoes, prophase, metaphase, anaphase, and finally telephase. When a cell actually separates the nuclear envelope and nucleus disappear leaving the chromosomes to replicate and then separate to opposite ends of the cell. The two identical chromosomes pairs are pulled apart by the spindle fibers (not shown). As the two daughter pairs fully separate and move to opposite ends the cell membrane pinches and two new daughter cells are made. In my photo the cell membrane is now represented by the tennis ball. The golf ball represents the nuclear envelope also separating as two new cells are made and the chromosomes are again shown as purple and green. The two stages this photo best represents is the metaphase and anaphase stages. In the first stage prophase, the nuclear envelope starts to break apart and spindle fiber start to appear. In the metaphase the chromosomes line up in the center or equator. In the anaphase the sister chromatids separate and move towards the poles. Of course in the final stage the nuclear envelope reappears as well as the nucleus and you have two new cells. This is a complicated process and I tried to simplify the process and show and accurate representation of the two of the four stages.

Here is the golgi apparatus, lysosomes, and a secretory vesicle. The golgi apparatus takes proteins and process them for shipping to other parts of the cell or its neighbors. When I think of the golgi apparatus I think of a factory taking in raw materials (the proteins) and carefully preparing them for shipping to there final destination. The golgi apparatus is shown as a miniature wooden factory. The lysosomes are one of the few organelles in the cell where I used a little more imagination to show the basic function. The lysosomes are made from the golgi apparatus and have enzymes which help break down incoming molecules from outside the cell membrane. Here I have a small monster of some sort eating (breaking down) a molecule making it ready for the cell to use elsewhere, good job enzyme. The last component in the photo is a secretory vesicle which is taking a packaged protein to the cell membrane where exocytose will export the protein outside of the cell. The vesicle is a sowing thimble filled with cell plasma.

Here is a good look at the mitochondria (battery) and the ATP (eraser tops) it produces. The mitochondria is the power producer of the cell and ATP is the primary source of energy. Mitochondria takes in simple sugars normally as glucose and produces ATP (adenosine triphosphate) the cells energy. Since a battery is the source of power for many household electronics it seemed a good representation for mitochondria.

Here is one of my favorite photos of the cell. You can clearly see many of the components and organelles in a nice display with the upper cytoskeleton and the protein on top. Proteins have a different shape for each different chemical reaction they cause. In this case the protein at the top of the cytoskeleton is connected to the cell membrane showing one of the ways molecules inside the cell can enter or leave. There are generally five different ways molecules can enter or leave a cell: diffusion, osmosis, facilitated transport, active transport, and endocytosis and exocytose. For my model I am showing facilitated transport, the protein (red circular foam pad) will allow proteins to cross the plasma membrane.

This is the top view of my cell and shows the cell membrane fully covering the upper portion of the cell and the facilitated transport protein embedded with the two bi-layer lipids which from the plasma membrane (blue tinted cellophane).

The last photo is a side view of the cell and I think just helps to show the full three dimensional effect.

In conclusion this lab project was a lot of fun to make and equally time consuming. The main concept I have learned from this lab is cells are very complicated and complex. It was challenging just to build a model which showed the basics of a cell, let alone all the other aspects and processes a cell does thousands of times a day. I think my cell model would give an unfamiliar reader an idea of what is involved in cellular metabolism and reproduction.