Somatic nervous system skeletal and muscular contaction Flashcards
1
Q
what doses peripheral nervous system control?
A
Controls movement of skeletal muscles
- Voluntary movement
2
Q
Ascending tracts
A
relay information from the spinal cord to the somatosensory cortex
3
Q
Descending tracts
A
relay information from the motor cortex to the spinal cord
4
Q
Sensory neurone
A
- Sense touch, stretch, pain etc.
- Relay information to spinal cord and brain
- Enter spine at the dorsal horn, via dorsal root
- Unipolar neurones – cell body is at dorsal root ganglion
- Myelinated - speed action potential
5
Q
Motor Neurones
A
- Relay nerve impulses from the spine to trigger
- Contraction of skeletal muscle
- Exit spine via ventral root
- ONE Alpha motor neurone
- Multipolar and myelinated
6
Q
Neuromuscular junction
A
- Acetylcholine is the neurotransmitter at skeletal muscle NMJs
- Shwann cell surrounds the presynaptic cleft ensure transmission
- Binds to and activates Nicotinic Acetylcholine receptor which is Ionotropic ligand gated reponds quick
- Post synaptic membrane termed Motor End Plate (MEP)
7
Q
skeletal striated
A
- Enables movement of limbs and other parts of the skeleton
- Connected to bone
- via tendons (origin)
- via tendons (insertion)
8
Q
Cardiac striated
A
- The pump in the circulation (heart)
- Functional syncytium
- Intrinsic pacemaker activity
9
Q
Smooth muscle
A
- Functional syncytium
Around many hollow internal organs
10
Q
Structure of muscle fibre
A
- Muscle belly
- Fasciculus
- Sarcolemma
- Sarcoplasm & sarcoplasmic reticulum
- Myofibrils
11
Q
Protiens involved in contraction
A
- Myosin
- Actin
- Troponin
- Tropomyosin
12
Q
I band
A
- Contains only actin filiments
13
Q
A I zone
A
- Consists of both the A and the I band
14
Q
H zone
A
Just contains the mysoin filiments
15
Q
Z discs
A
- At the terminal ends of the sarcomere
- 1 sarcomere holds the actin filiments
