Skeletal Muscle Contraction & Energetics

This week we will be learning how skeletal muscle contracts. The mechanism of contraction involves the contractile apparatus within the myofibrils... therefore, make sure that you understood the sarcomere as described in Unit 7 before continuing on here.

We will begin this week by adding to our knowledge of the sarcomere and of the microfilaments that make it up. With this additional information, we will be able to make the transition from an understanding of the anatomy of a sarcomere to an understanding of the way the sarcomere moves. This is difficult, but exciting, information. We will also investigate how our bodies deal with the energy requirements of muscle contraction.

Here are the main ideas for this week:

microfilaments are proteins with dynamic qualities

	myosin
	actin & associated proteins

	ATP is necessary for muscle contraction
	the Sliding Filament Theory
	as sarcomeres shorten, muscle fibers shorten, and the entire muscle shortens
	How do we get the energy we need for contraction?

You will need to go forward on the Marieb CD to the chapter on the sliding filament theory in order to understand this material fully.