Chapter Summary

After reading through these past sections, you should have a greater understanding of the principles behind cell communication. Movement of molecules and ions across the cell membrane can be achieved through different mechanisms that are important for the proper functioning of a cell. Movement of ions in and out of the cell effects the membrane potential of the cell. When the membrane potential is increased high enough to above threshold, an action potential (AP) will occur. An AP propagating down a neuron and synapsing onto a muscle cell via the neuromuscular junction is the mechanism behind the signaling to a muscle to contract. The AP then travels down the skeletal muscle fiber, causing a contraction through the formation of cross bridges between actin and myosin myofilaments .

Chapter Review Quiz

Test your knowledge with this question set that includes 25 different questions to review major concepts throughout this unit. Please note these questions are not to serve as a final review but to ensure that big concepts are understood. All details of this unit are not included in this section and therefore, should not be used as a sole study tool.