Neurons and Nerve Signals

Use Neurons and Nerve Signals first, then Reflex Arcs and Reaction Time Data, which builds on the same cells. Gas Exchange in the Alveoli stands alone and works well beside a lesson on the respiratory system.

Label a neuron, then number the six steps a nerve signal takes across dendrites, axon and synapse. The directions on the page read: Read the text. Then write a word or term from the bank in each box on the diagram. An answer key is included.

Yes, both. We made it for 7th grade living things, and it works the same at home or at school. At home, a student can work through it alone and then go over it with you, which shows quickly what is solid and what needs another look. In class it works as independent practice, homework or a warm-up, and you can print one copy or a full set.

Dendrites receive the signal and pass it to the cell body. It then travels along the axon, where myelin lets it jump between gaps, and chemicals carry it across a synapse to the next cell. Neurons and Nerve Signals has students number these steps.

A reflex arc is the path of a fast, automatic response. A receptor detects the stimulus, a sensory neuron carries the signal to the spinal cord, an interneuron passes it to a motor neuron and a muscle contracts. Reflex Arcs and Reaction Time Data has students name each part.

Oxygen and carbon dioxide diffuse, moving from where they are more concentrated to where they are less concentrated. The wall of an alveolus is one cell thick and capillaries wrap around it. Gas Exchange in the Alveoli compares gas percentages in inhaled and exhaled air.