Students often have difficulty visualizing cell structure when can see it only in a textbook. Building a model of a cell, be it plant or animal, helps students learn in a hands-on way that enhances recall and understanding. Crafting a three-dimensional cell also helps students gain an idea of the size of the different organelles in comparison to each other. It is a simple, fun-to-do craft that yields excellent results.
The Cell Wall
The most important structure of the plant cell--and what separates it from animal cells--is the cell wall. The cell wall is a rigid structure that provides support and protection while still allowing gas transfers across the membrane.
To represent the cell wall in your model, use a plastic, see-through shoebox-sized container, a cardboard shoe box or an aluminum foil pan.
The cell membrane is a semi-permeable membrane that allows some materials to pass through the cell, while excluding other materials. It helps the cell maintain homeostasis and offers additional support and protection.
Use clear plastic wrap to represent the cell membrane.
The nucleus is the information center of the cell. DNA, the genetic material, resides inside the nuclus. It is the DNA that holds the plans for all the proteins needed to sustain life.
A ping pong ball, the ball from a deodorant or a small ball made of modeling clay can represent the nucleus. If you want to be really fancy, you can carefully cut open the ping pong ball and put strands of yarn inside to represent the DNA. You can then tape the ball shut or leave it open to show the contents.
This is the goo in which all the other organelles reside. It adds additional support to the cell and protects the organelles.
When creating a cell model, it is helpful to start with the cytoplasm. Clear gelatin makes an excellent visual representation. Prepare the gelatin as directed on the package, except use half the water recommended. Pour the gelatin into the "cell wall" and over the cell membrane. Let it chill in the refrigerator for 45 minutes to an hour. Once it has set a little you can add the other cell components.
Endoplasmic Reticulum and Ribosomes
These are the "tubes" that carry materials through the cell. There are two different types of E.R.--rough and smooth. Ribosomes attached to the E.R. give it a bumpy appearance. The smooth E.R. moves the newly produced proteins to the golgi body and other organelles.
Ribosomes are responsible for the protein production.
Cooked spaghetti, yarn or gummy worms can represent the E.R. To emphasize the difference between smooth and rough E.R., coat approximately half of the cooked spaghetti or yarn with cracker crumbs or nonpareils (candy dots). Dip the materials in paste first, so the "ribosomes" will stick.
This bean-shaped organelle is the powerhouse of the cell. It breaks glucose into adenosine triphosphate. ATP fuels the reactions needed to sustain cell life. Without the mitochondrion, the cells could not transfer the energy of glucose into a more accessible form.
Pinto-beans, modeling clay or raisins can represent the mitochondria. A raisin captures the rough surface of the organelle perfectly.
Vacuoles are fluid filled sacs that store water and food for future use. Plants have to store a large amount of food, so vacuoles occupy a large percentage of the cell--most cells having only one large one. A plastic zipper baggie filled with water or plastic bubble wrap can represent a vacuole.
The lysosomes are round organelles that break down larger food molecules into smaller ones. They also perform the valuable function of digesting old cell parts.
Small balls of modeling clay or M&M candies can represent these cell parts.
Photosynthesis occurs in the chloroplasts. They contain the chlorophyll, which captures energy from the sun and transforms it into glucose. Chloroplasts make plants capable of producing their own food.
Green modeling clay shaped like pancakes or green plastic beads can represent the chloroplasts.
Putting it All Together
When assembling the plant cell model, it is helpful to get everything together while the gelatin is setting. Then you merely have to place all the organelles in the gelatin, and your model is complete. You will want to make a key to show what the pieces represent.