Neuromuscular System

Question 1

Autonomic Nervous System

Answer 1

Regulates function of internal organs such as heart and also controls some skeletal muscles

Question 2

Sympathetic nervous system

Answer 2

Prepares the body for exercise and is often referred to as the ‘fight or flight response‘

Question 3

Parasympathetic Nervous System

Answer 3

Relaxes and slows down high energy functions in the body

Question 4

3 types of Muscle fibres

Answer 4

. Type 1 (slow oxidative)
. Type 2a (fast oxidative glycolytic)
. Type 2b (fast glycolytic)

Question 5

Characteristics of Type 1 (slow twitch)

Answer 5

. Slow Contraction speed 
. Produce energy aerobically (V High aerobic capacity) 
. Slow motor neurone size
.  Low Fatiguability
. Low ATP enzyme activity

Question 6

Characteristics of type 2a (fast twitch)

Answer 6

. Fast contraction speed 
. Produce most energy anaerobically (Medium Aerobic capacity, high anaerobic) 
. Medium Fatiguability 
. Large motor neurone size 
. High ATP enzymes activity

Question 7

Characteristics of type 2b (fast twitch)

Answer 7

. Fast contraction speed 
. Produces most energy anaerobically (Low aerobic capacity and V High anaerobic) 
. High Fatiguability 
. Large motor neurone size 
. V High ATP enzyme rate

Question 8

A motor unit is

Answer 8

A motor neurone and its muscle fibres

Question 9

Motor neurones are

Answer 9

Nerve cells which transmit the brain’s instructions as electrical impulses to the muscle

Question 10

Neuromuscular Junction

Answer 10

Is where the motor neurone and muscle fibre meet

Question 11

How does muscle contraction occur

Answer 11

. Muscle spindle senses muscle stretching
. Impulses sent down sensory neurone to spinal cord
. Then down the motor nerve to the muscle again
. Then as a result of the muscle stretching the muscle contracts

Question 12

All or None Rule

Answer 12

Where once the motor neurone stimulates the muscle fibres either all of them contract or none of them do. (Partial contraction isn’t possible)

Question 13

3 phases of single twitch

Answer 13

. Latent period
. Period of contraction
. Relaxation period

Question 14

Wave summation

Answer 14

Greater frequency of stimuli the greater tension developed by the muscle

Question 15

Spatial Simulation

Answer 15

Occurs when impulses are received at the same time at different places on the neurone which add up to fire the neurone

Question 16

Titanic contraction (or tetanus)

Answer 16

Sustained muscle contraction caused by a series of fact repeating stimuli

Question 17

Muscle Spindles definition

Answer 17

Detect how far and fast a muscle is being stretched and produce the stretch flex

Question 18

Golgi tendon organs

Answer 18

Activated when there is tension in a muscle

Question 19

PNF in practice

Answer 19

a) Individual performs stretch (helped by partner) and extends leg till tension. Stretch detected by muscle spindles. (Stretch reflex occurs if muscle stretched too far)
b).Individual isometrically contracts (10 sec) muscle by pushing leg against partner pushing against leg (holds leg stationary).
. During this Golgi tendons are sensitive to tension in muscle due to isometric contraction, they are activate
. This inhibits override signals of spindles therefore delaying stretch reflex
c). Leg lifted again, Golgi tendons responsible for antagonist muscle relaxing, meaning leaf stretches further. Process can be repeated till no more gains are possible

Question 20

Isometric

Answer 20

Wheee muscles contract but stay the same length

Question 21

Muscle Spindles and Golgi tendons are examples of

Answer 21

Proprioceptors