Nervous System: Divisions, Function + Muscle Contraction (w4) Flashcards
What does the somatic nervous system control ?
It controls the movement of skeletal muscles.
What two divisions are in the autonomic nervous system ?
- parasympathetic division
-sympathetic division
What are the two control centres is the brain (cortex) ?
- Somatosensory cortex
- Motor cortex
What do ascending tracts do ?
They relay information from the spinal cord to the sensory cortex.
What do descending tracts do ?
They relay information from the motor cortex to the spinal cord.
What are sensory neurones, and what do they do ?
They are myelinated neurones which relay information to the spinal cord and the brain.
They sense touch, stretch and pain.
What are motor neurones and what do they do ?
They are multipolar and myelinated neurones which relay nerve impulses from the spine to trigger contraction of the skeletal muscle.
What is a unipolar neurone ?
A neurone which has a cell body at dorsal root ganglion.
For example; Sensory neurone
What makes up a neuromuscular junction (NMJ) ?
A synapse somatic motor neurone and a muscle fibre.
What neurotransmitter is at the skeletal muscle neuromuscular junctions ?
Acetylcholine
What is the motor end plate (MEP) and what do you find here ?
The MEP is the post synaptic membrane and you find the chollinergic receptors.
Describe the function of skeletal (striated) muscle and how it is connected to bones ?
- It enables the movement of limbs and other parts of the skeleton and is connected to bone via tendons (origin) or via tendons (insertion).
Describe the function of cardiac (striated) muscle ?
Cardiac muscle is the pump in the circulation system (heart). It has intrinsic pacemaker activity and is myotonic.
Where is smooth muscle found ?
Around many hollow internal organs.
What is the cytoplasm of a muscle fibre called ?
Sarcoplasm
List the 4 key proteins involved in contraction;
- Myosin
- Actin
- Troponin
- Tropomyosin