Although not actual size, this active transport model is the perfect tool for teachers to demonstrate to students how molecules are moved against their concentration gradients through a membrane and into a cell. This product represents the process of an active transport protein transporting molecules from their low concentration to their high concentration.
When a cell needs to maintain a high concentration of one substance and/or a low concentration of another, these substances must be moved against their concentration gradients(their natural flow). This means normal diffusion through a membrane will not work and an active transport protein is needed. This special protein binds to a specific substance, closes the opening on one side of the membrane, and creates an opening on the other side. In order for the protein to change its shape, exergonic energy from the breaking down of adenosine triphosphate into adenosine diphosphate and a single phosphate is needed. This whole process is referred to as Active Transport.
Being such a challenging concept to grasp, as a student, I have suffered from the struggle teachers have trying to illustrate this process in a way students comprehend. This is why I have created this model, to be an aid for teachers and students. I highly recommend printing this design. Students will excel in class, for this model brings the textbook to life.
This model is an assembly of 25 total printed pieces (12 different pieces), a piece of wood, and two different types of magnets. After a tediously long time of printing, hand on adjustments, sawing, taping, and gluing must be done following the directions below.
After successfully printing each piece, more work must be put into this project to prepare it for presentation material. Please follow the following steps carefully.
1. To create friction for the rotating proteins against gravity, scotch tape must be wrapped around the knobs.
2. To create friction to prevent the pegs from falling out, scotch tape must be added to the underside of these two pieces.
3. The pegs extruding from the sphere substances, cube substances, and single phosphate might need to be clipped down at the corners to make the removal and placement of them within the protein easier.
4. The hole of the single phosphate must be filled with hot glue and then the long magnet must be pushed into place within it.
5. The hole of adenosine diphosphate must be heated up with a heat gun and then the fat magnet must be pushed into place within it.
6. The five base plates should be placed onto a piece of relatively thin wood with the pegs in the main plate notches. The outline of these plates should be drawn and a jigsaw must carefully cut out this outline.
7. The five base plates should be glued onto this wood plate using hot glue.
8. Using hot glue, the eight substances of the concentration plate should be glued into place since none have to be moved throughout use. Three cube substances and one sphere substances should be glued to the blue concentration plate. Three sphere substance and one cube substance should be glued to the pink concentration plate.
9. Slide each protein onto its peg and slide the plugs in to open whole of each protein.
Plate: This plate is designed with two knobs extruding from the surface and four engravings on the bottom. The protein halves slide onto and rotate on each knob. They are designed with revolved bosses all around to ensure easy rotation for the proteins. They also consist of an expansion of the diameter towards the top, which matches the inside on the proteins, and makes it impossible for the proteins to be pulled off the knobs. To ensure the knobs don't break off the plate, a fillet was added, blending them into the surface of the plate. The engravings on the North, South, East, and West of the bottom of the plate line up with the extruding pegs of the membranes and concentration plates, which each have designate placements.
Membrane: Although one stl, this piece should be printed twice. The extruding pegs fit into the engravings of the underside of the plate (the West and East ones). The curved sides of this piece match up perfectly with the sides of the plate. This piece resembles the phospholipid bilayer membrane that the protein is bonded into.
Concentration: Although one stl, this piece should be printed twice. The extruding pegs fit into the engravings of the underside of the plate (the North and South ones). The curved sides of this piece match up perfectly with the top and bottom of the plate. This piece is equipped with placeholders for the two substances. Both printed in different colors, the blue concentration plate resembles the extracellular matrix and the pink one resembles the cytoplasm. Where the concentration of the sphere substance is higher in the cytoplasm, there are three sphere substances in the pink piece and one in the blue piece. Where the concentration of the cube substance is higher in the extracellular matrix, there are three cube substances in the blue piece and one in the pink piece. This shows students how the substance flow from an area of low concentration to an area of high concentration, against their concentration gradient.
Left Half of Protein: This half of the protein contains the holder for three sphere substance. The protein contains a cut on its underside that the plate knobs can slide into. This cut ends with a semi revolved cut that allows easy rotating. The engravings for the pegs of the sphere substances are at a forty-five-degree angle that allows the substances to have a tight four-sided fit while still being able to be taken in and out of the protein.
Right Half of Protein: This half of the protein contains the holder for two cube substance and the single phosphate. The protein contains a cut on its underside that the plate knobs can slide into. This cut ends with a semi revolved cut that allows easy rotating. The engravings for the pegs of the cube substances are closer to one corner of the placed cube, creating a tight four-sided fit. The phosphate peg engraving is at a forty-five-degree angle that allows the substances to have a tight four-sided fit as well and making it easy to take it in and out of the protein.
Protein Plugs: These pieces plug into the vacant space left by the peg cuts of the proteins. Being a perfect fit, they blend right into the protein shapes while stabilizing the proteins onto the pegs. They also contain extruded rectangles on the exterior ends that can be used to grab and pull out if the proteins must be taken off.
Sphere Substance: A total of seven pieces must be printed for this piece. Supports must be added to this piece when being printed.
Cube Substances: This piece must be printed a total of six.
Adenosine Triphosphate: The single phosphate must be bonded with a short, wide cylindrical neodymium magnet with a diameter of 1.3 cm and a width of 0.5 cm. The Adenosine Diphosphate must be bonded with a long, skinny neodymium magnet with a diameter of 0.6 cm and a legnth of 2 cm. With these two magnets a part of these pieces, they will be able to bond together and break apart easily.
Wood: A piece of wood should be used to glue the other plates onto. Although the thickness does not really matter, it should be thin enough for a jigsaw to easily carve through it. In this example, a piece of wood with a width of 0.3 cm was used.
Stand: This stand holds the whole model up at a 70-degree angle making teachers' presentations run more smoothly; the model is now more visible to students and teachers can smoothly maneuver pieces with two hands