Flashcards in Physiology Deck (11):
1
Types of muscle
Skeletal, smooth and cardiac
2
Striated muscles
Cardiac and skeletal
3
One motor unit consists of:
A single motor neuron and all its connecting muscle fibres (muscle fibres are muscle cells).
4
The more muscle fibres to a motor unit the..
Less refined the action will be.
5
The fewer muscle fibres to a motor unit the..
More precise an action will be e.g. muscles in the eye, hand movements etc
6
What are muscle cells made up of? What is the functional unit within them?
Myofibrils- the functional units with muscle cells are sacromeres.
7
What do sacromeres contain?
Actin (thin) and myocin (thick) filaments.
8
How is muscle contraction brought about?
Calcium is released from lateral sacs of the sacroplasmic reticulum when an action potential passes. The AP passes down T tubules. The calcium then binds to troponin creating tropomyosin which causes cross bridge formation of actin and myocin.
9
In sacromeres, describe the H zone
Thin filaments don't reach
10
In sacromeres describe the M line
Extends vertically down the middle of the A band in the centre of the H zone.
11