Part 1.1, Skeletal and muscular systems

Question 1

What is a motor unit?

Answer 1

A motor neuron and the muscle fibres stimulated by its axon

Question 2

What is a motor neuron?

Answer 2

A nerve cell which conducts a nerve impulse to a group of muscle fibres

Question 3

What is an action potential?

Answer 3

Positive electrical charge inside the nerve and muscle cells which conducts the nerve impulse down the neuron and into the muscle fibre

Question 4

What is a neurotransmitter?

Answer 4

A chemical (acetylcholine) produced and secreted by a neuron which transmits the nerve impulse across the synaptic cleft to the muscle fibre

Question 5

What is the all-or-none law?

Answer 5

Depending on whether the stimulus is above a threshold, all the muscle fibres will give a complete contraction or no contraction at all

Question 6

Articulating surfaces at the knee

Answer 6

Femur and tibia

Question 7

Articulating surfaces at the elbow

Answer 7

Radius, ulna and humerus

Question 8

Articulating surfaces at the shoulder

Answer 8

Humerus and scapula

Question 9

Articulating surfaces at the hip

Answer 9

Pelvis and femur

Question 10

Articulating surfaces at the wrist

Answer 10

Radius, ulna, carpals

Question 11

Articulating surfaces at the ankle

Answer 11

Tibia, fibula and talus

Question 12

Four quadriceps

Answer 12

Vastus medialis
Vastus intermedius
Vastus lateralis
Rectus femoris

Question 13

Three hamstrings

Answer 13

Semimembranosus
Semitendinosus
Bicep femoris

Question 14

Agonist during plantar flexion

Answer 14

Gastrocnemius and soleus

Question 15

Agonist during dorsi-flexion

Answer 15

Tibialis anterior

Question 16

What are the 5 joint types, with examples

Answer 16

Hinge joint - elbow
Ball and socket joint - shoulder
Condyloid joint - wrist
Pivot joint - radio-ulna
Gliding joint - spine

Question 17

Sagittal plane

Answer 17

Lies vertically and divides the body into left and right parts from the medial to the lateral

Question 18

Frontal plane

Answer 18

Lies vertically and divides the body into anterior and posterior parts

Question 19

Transverse plane

Answer 19

Lies horizontally and divides the body into anterior superior (upper) and inferior (lower) parts

Question 20

Horizontal flexion

Answer 20

Movement of the limbs towards the midline of the body parallel to the ground

Question 21

Horizontal extension

Answer 21

Movement of the limbs away from the midline of the body parallel to the ground

Question 22

Rotation

Answer 22

Movement whereby articulating bones turn about their longitudinal axis in a screwdriver action

Question 23

Fixator

Answer 23

A muscle that stabilises the body whilst another moves

Question 24

Agonist and antagonist of flexion at the hip

Answer 24

Agonist - iliopsoas
Antagonist - gluteus maximus

Question 25

Concentric contraction

Answer 25

When a muscle shortens producing tension. E.g. upward phase of a bicep curl

Question 26

Eccentric contraction

Answer 26

Muscle lengthens producing tension. E.g. downward phase of a bicep curl

Question 27

Isometric contraction

Answer 27

Muscle contracts but does not change length. E.g. pectoralis major during a plank

Question 28

Name the three types of muscle fibre

Answer 28

Slow oxidative
Fast oxidative glycolytic
Fast glycolytic

Question 29

Slow oxidative:
Neuron size
Fibres per neuron
Capillary density
Mitochondria density
Myoglobin content
Phosphocreatine store

Answer 29

Neuron size - small
Fibres per neuron - few
Capillary density - high
Mitochondria density - high
Myoglobin content - high
Phosphocreatine store - low

Question 30

Slow oxidative:
Speed of contraction
Force of contraction
Fatigue resistance
Aerobic capacity
Anaerobic capacity
Sport

Answer 30

Speed of contraction - slow
Force of contraction - low
Fatigue resistance - high
Aerobic capacity - high
Anaerobic capacity - low
Sport - marathon runner

Question 31

Fast oxidative glycolytic:
Neuron size
Fibres per neuron
Capillary density
Mitochondria density
Myoglobin content
Phosphocreatine store

Answer 31

Neuron size - large
Fibres per neuron - many
Capillary density - high
Mitochondria density - moderate
Myoglobin content - moderate
Phosphocreatine store - high

Question 32

Fast oxidative glycolytic:
Speed of contraction
Force of contraction
Fatigue resistance
Aerobic capacity
Anaerobic capacity
Sport

Answer 32

Speed of contraction - fast
Force of contraction - high
Fatigue resistance - moderate
Aerobic capacity - moderate
Anaerobic capacity - moderate
Sport - 800m runner

Question 33

Fast glycolytic:
Neuron size
Fibres per neuron
Capillary density
Mitochondria density
Myoglobin content
Phosphocreatine store

Answer 33

Neuron size - large
Fibres per neuron - many
Capillary density - low
Mitochondria density - low
Myoglobin content - low
Phosphocreatine store - high

Question 34

Fast glycolytic:
Speed of contraction
Force of contraction
Fatigue resistance
Aerobic capacity
Anaerobic capacity
Sport

Answer 34

Speed of contraction - fast
Force of contraction - high
Fatigue resistance - low
Aerobic capacity - low
Anaerobic capacity - high
Sport - 100m sprint

Question 35

What is phosphocreatine?

Answer 35

A high energy compound stored in the muscle cell used as a fuel for very high-intensity energy production

Question 36

What is myoglobin?

Answer 36

A protein in the muscle responsible for transporting oxygen to the mitochondria