Cholinergic synapses (CIE A-level Bio)

This lesson describes the structure of a cholinergic synapse and outlines the role of these connections in the nervous system. The fully-resourced lesson has been designed to cover the content of point (9) of topic 15.1 of the CIE A-level biology specification (for assessment in 2025-27). The majority of the lesson uses the cholinergic synapse as the example but other neurotransmitters are considered at the end of the lesson to provide the students with a wider view of this topic.

One of the tasks near the beginning of the lesson challenges students to identify 3 terms from a WALL of key terms that could follow synaptic, having been introduced to the synaptic cleft on the previous slide. Not only will this challenge their prior knowledge from lessons earlier in topic 15 but it will also lead to the discovery of four of the structures that are found in a synapse. Moving forwards, students are introduced to acetylcholine as the neurotransmitter involved at cholinergic synapses and they will start to add labels to the structures found in the pre-synaptic bulb. Time is taken to focus on certain structures such as the voltage gated channels as these types of channel were met previously when looking at the depolarisation of a neurone. There is plenty of challenge and discovery as students are pushed to explain why organelles like mitochondria would be found in large numbers in the bulb. With this process being a cascade of events, a bullet point format is used to ensure that the key content is taken in by the students and again key points like exocytosis and the action of acetylcholinesterase are discussed further. The final part of the lesson challenges the application aspect of the subject as students are introduced to unfamiliar situations in terms of synapses with new drugs like MDMA and are asked to work out and explain how these affect the nervous transmission.

Understanding checks and prior knowledge checks are included throughout the lesson so that students can not only assess their progress against the current topic but also see whether they can make links to earlier topics.