key information needed to know before lecture on movement

Question 1

what is smooth muscle?

Answer 1

located in the inner walls of our internal organs

responsible for maintaining supply of food and fluid in the internal organs

they are self stimulated- no action of NS needed

Question 2

cardiac muscle

Answer 2

located in the hear
automatically generated
it allows your heart to pump blood throughout your body

Question 3

skeletal muscle

Answer 3

responsible for movement and locomotion of our body.
located under skin and bones
these require stimulation of our nervous system via motor neurons

Question 4

Explain the process of muscle contraction

Answer 4

1- thin (actin) and thick (myosin) filaments slide past eachother
2. sarcomere contains actin and mysoin
3-actin is blocked by troponin and tropomyosin
4-sarcoplasmic reticulum contains calcium pumps. calcium rushes into cell so troponin binds to calcium
5- this changes the shape of troponin causing it to move and causing tropomyosin to also move
6- this means the actin sites are free for myosin to bind to them (ATP needs to convert first)
7- as it binds it gives all the energy and changes shape causing of the sarcomere causing it to shrink thus contracting the muscle

Question 5

what are alpha motor neurons?

Answer 5

large multipolar lower motor neurons of the brainstem and spinal chord
they innervate extrafusal muscle fibres of skeletal muscle and are directly responsible for initiating their contraction

Question 6

Explain the action in Neuromuscular junction

how does a contraction occur?

Answer 6

neuromuscular junction is the synapse between a motor neuron and a muscle fibre

1. Ap in motor neuron
2. Then Release of Ach in synaptic cleft
3. Excitatory post synaptic potential-EPSP in muscle fibre
4. AP in muscle fibre
5. Contraction (twitch)