This concise lesson covers the content of specification point 5.1.5 (l) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply an understanding of the action of neuromuscular junctions. Due to a number of similarities between these structures and cholinergic synapses, this lesson uses prior knowledge of these connections between neurones to build a good understanding of the junctions. Students will discover that the events that occur at an axon tip mirror those which happen at the pre-synaptic bulb and this is then developed to look at the differences in terms of the events once the acetylcholine has bound to its receptor sites. There is a focus on the structure of the sarcolemma and time is taken to explain how the action potential is passed from this membrane to the transverse tubules in order to stimulate the release of calcium ions from the sarcoplasmic reticulum. As a result, this lesson ties in nicely with the following lesson on the contraction of skeletal muscle and students will be able to link the binding to troponin in that lesson to the release of these ions from this lesson.
Both of the main tasks of the lesson have been differentiated so that students of all abilities can access the work and make progress.
This lesson has been designed for those students studying on the OCR A-level Biology course and ties in nicely with the other uploaded lessons on module 5.1.5 (Animal and plant responses)