Skeletal, smooth & cardiac muscle (OCR A-level biology)

This lesson describes the differences between skeletal, smooth (involuntary) and cardiac muscle. The PowerPoint and accompanying resources form part of the 1st lesson in a series of 3 lessons which have been planned to cover the content of point 5.1.5 (l) (i) of the OCR A-level biology A specification. The other two lessons are “neuromuscular junctions” and “the sliding filament model of muscular contraction”.

The lesson begins with a bit of fun by challenging the students to identify the prep room skeleton from a description and then to recognise that the reason the skeleton doesn’t have free movement or locomotion is because “he” lacks muscles. More specifically, it is the lack of skeletal muscles which prevents bones from moving and this leads into the introduction of this type of muscle tissue as being attached to bones. Time is taken to consider tendons, and more specifically the protein collagen, and students are challenged on their recall of this fibrous protein from module 2.1.2. This lesson contains numerous prior knowledge checks like this, to encourage them to identify the links between topics and modules. All answers to these prior knowledge and understanding checks are embedded into the PowerPoint to allow the students to assess their progress. The structure of skeletal muscle is covered in the 3rd lesson in this series, but this lesson does focus on the structural and functional differences between smooth and cardiac muscle. Students are introduced to intercalated discs and gap junctions in cardiac muscle and are challenged to explain how these features support the stages of the cardiac cycle. Earlier in this module, they covered the regulation of heart rate and a SPOT THE ERRORS task will challenge the detail of their knowledge of this control system. The remainder of the lesson focuses on smooth muscle, using examples in the gut wall, iris and arterial walls to increase relevance.