muscular revision

Question 1

describe type 1 slow oxydative fibres

Answer 1

good for prolonged sport activities due to lots of mitochondria and highly resistant to fatigue. Low contractile speed and force. high areobic capacity.

Question 2

describe fast oxydative glycolytic fibres

Answer 2

are both fast and slow, still resistant for fatigue but used to more endured power movements such as 800m or something. higher but low contractile speed and force.

Question 3

describe fast glycolytic fibres

Answer 3

powerful and quick movements, weightlifting, high force and speed and anaerobic capacity, not resistant to fatigue.

Question 4

what are motor neurons

Answer 4

nerve that transmits electrical signals to muscles.

Question 5

explain how the motor neuron cycle works with AP

Answer 5

AP is generated in the soma which is then recieved by the dendrite - this then goes along the axon which passes this down the motor neuron - this then splits the axon and the AP reaches the neuromuscular junction (synapse) and a fassicle. The neuromuscular junction is mentioned in other card.

Question 6

explain what happens at the neuromuscular junction when AP reaches it

Answer 6

AP stimulates the release of acetylecholine (ACE) from the synaptic vessicles - ACE fills the synaptic cleft - ACE travels into muscle fibre - if there is enough ACE then AP can be conducted into muscle fibre and generates an excitory post synaptic AP (esap) - if esap is big enough then this will cause a muscular contraction & release of calcium ions.

Question 7

what is a sarcomere

Answer 7

functional unit of a myofibril, where shortening and lengthening occurs.

Question 8

explain the sliding filament theory

Answer 8

The sliding filament theory explains how muscles contract to produce movement. It describes the interaction between two main protein filaments in muscle fibers: actin (thin filaments) and myosin (thick filaments). During contraction, the myosin heads attach to binding sites on the actin filaments, forming cross-bridges. These cross-bridges then pull the actin filaments towards the center of the sarcomere, causing the muscle to shorten and generate force. This process requires energy in the form of ATP. As the actin filaments slide past the myosin, the muscle fiber contracts, resulting in movement.

Question 9

describe role of tropomyosin

Answer 9

prevents muslce contraction/ power stroke as it surrounds the actin. This covers binding sites which prevents the formation of cross bridges.

Question 9

try your best to explain the structure of a sarcomere

Answer 9

Z lines on left edge attached to actin. Actin filaments on the left side. M lines in the middle. then myosin on the right. then another Z line on the right which binds with the myosin. On the bottom there are I bands on the left and right sides and an A band in the middle. (I bands only contain actin).

Question 10

describe what it means: isometric, isotonic, concentric, eccentric.

Answer 10

same length
same energy
muscle gets shorter
muscle gets longer