T1 U9 Skeletal muscle activity

Question 1

What are the functional characteristics of skeletal muscle

Answer 1

Excitability
Contractility
Extensibility
Elasticity

Question 2

What is a motor unit

Answer 2

One neuron + all skeletal muscle cells

Question 3

Name the path a stimulus travels

Answer 3

Axon -> Axon terminal -> Neuromuscular junction -> Vesicles -> Neurotransmitter -> ACH

Question 4

Name the order of the 4 phases of Skeletal muscle contraction

Answer 4

Cross-bridge attachment
Working / power stroke
Cross-bridge detachment
Cocking myosin head

Question 5

Explain sliding filament theory

Answer 5

Muscle fibres activated and myosin heads attach to binding sites and sliding begins

Each attachment and detachment causes tension generation which helps pull thin filaments toward centre of sarcomere

Cell shortens but not myofilaments

Question 6

Describe the graded response contraction

Answer 6

Whole muscle reacts to stimuli in 2 ways

• change frq of muscle stimuluation
• Change number of muscle cells stimulated at one time

Question 7

3 ways of ATP regeneration

Answer 7

1) direct phsoporylation
2) aerobic respiration
3) Anaerobic glycolysis

Question 8

What causes muscle fatugue

Answer 8

Strenuous or prolonged exercise. Occur b/c O2 deficit causing lactic acid build up causing a decrease in ATP

Question 9

Effects of Aerobic execise

Answer 9

Incr. blood supply
Incr. metabolism
heart enlarges
more efficient lungs

Question 10

Effects of Resistance execise

Answer 10

Incr. muscle size + strength

Incr. muscle cell size