Nerve muscle IV

1. What is the bending of a limb at  a joint is known as.

Flexion

2. What is the cause of masthenia gravis?

Antibodies to muscle acetylcholine receptors

3. During muscle contraction, there is shortening of sarcomere length without change in length of either thick or thin filaments. What is this mechanism?

Sliding filament or ratchet theory

4. Stiffening of skeletal muscles following death is called as rigor mortis. What is the specific cause for rigor mortis?

Absence or dectease in levels of ATP

5. Where is foot proteins located in a muscle?

Lateral sacs of sarcoplasmic reticulum

6. What is a group of muscle fibres innervated by a single motor neuron called as?

A motor unit

7. What is a motor-end-plate?

Region of muscle membrane lying directly under a motor neuron at the NMJ

8. Why is it that the cardiac muscle cannot be tetanised?

It has long refractory period

9. What is the type of smooth muscle present in the uterus?

Unitary / single unit type

10. What are the folds of the muscles membrane underneath the NMJ called?

Palisades

11. What is the axonal nerve damage that does not completely severe the surrounding endoneurial sheath called?

Axonotmesis

12. What is the term used to describe an injury to a nerve that interrupts conduction causing temporary paralysis, but not degeneration, which is followed by complete recovery?

Neurapraxia

13. At which structure of the thin filament does that  Calcium ion  bind to durng muscle contraction?

Troponin C

14. What is an end-plate potential?

Local depolarization at the motor-end-plate

15. Name one area in a nerve muscle where inhibitory potentials do not occur generally.

Neuromuscular junction

( Physiology; UMS 2008 )