Movement ( + Textbook Chapter 7 ) Flashcards
Explain THREE things highlighting the relevance of the muscles in the context of biological psychology.
Muscles allow…
- Movement.
- Behavioural expression.
- Response to stimuli.
Define:
The quantal theory of neurotransmitter release.
Neurotransmitters are released from vesicles typically containing a similar number of molecules in each.
Increased stimulation leads to increased release of fixed ‘packages’ (vesicles).
List:
The THREE types of muscle cells.
- Smooth
- Striated
- Cardiac
Striated muscle cells are also known to be skeletal muscle cells.
What function does smooth muscle tissue serve?
Mobility and motility of internal organs.
What function does striated muscle tissue serve?
Support and movement of the skeletal system.
What function does cardiac muscle tissue serve?
Enabling the pumping action of the organ to power blood circulation.
Cardiac muscle cells are similar to striated, but appear more like a tangled network.
True or False:
One neuron can innervate multiple different skeletal muscle cells.
True
True or False:
Each muscle fibre receives information from only one neuron.
True
Because although each neuron can innervate many different fibres for coordinated stimulation, each fibre should only be receiving input from a single source for specialised activation.
State:
Each structural level of skeletal muscle.
In order from smallest unit to largest unit.
- Myofilaments (actin and myosin).
- Myofibrils (bundles of myofilaments).
- Sarcomeres (segments end to end along myofibrils).
- Muscle fibre (sarcomeres end to end).
- Skeletal muscle (group of muscle fibres).
What is the plasma membrane of a skeletal muscle cell more commonly referred to as?
Sarcolemma.
What is the ER of a skeletal muscle cell more commonly referred to as?
Sarcoplasmic reticulum.
Define:
Neuromuscular junction.
Where a neuron synapses with a muscle fibre.
Which neurotransmitter is the most essential for muscle innervation and contraction?
Acetyl choline.
What kind of receptors does acetyl choline typically bind to during muscle contraction?
Nicotinergic (ionotropic) receptors.
These lead to an influx of Na+ into the cell.
Muscle fibre contraction is similar to action potentials in the sense that it is described as…
…an ‘all or nothing’ response.
The fibre will either contract or it won’t.
What role does the sarcoplasmic reticulum serve during muscle contraction?
It releases stored Ca2+, which activates the sliding action of actin and myosin.
Describe:
The sliding filament theory of muscle contraction.
Contraction of a muscle fibre arises when myosin filaments ‘slide past’ actin filaments and shorten the distance between sarcomeres.
Motor neurons from which part of the spinal cord initiate contraction or movement of skeletal muscles.
(i.e. efferent neurons)
The ventral horn.
“Towards the belly”.
Activation of muscle cells always initiates…
…contraction.
Why is it important for the CNS to receive ‘feedback’ from the muscular system?
So that exact positioning may be known and subsequent appropriate activation.
What are the TWO types of ‘sensory organs’ of the skeletal muscle system?
-
Muscle spindle
& - Golgi tendon organs
Describe the role of muscle spindle.
Sends ‘stretch response’ sensory information to the dorsal root of the spinal cord.
This signal then bypasses the brain to activate a contraction response.
An example is seen in the knee-jerk reflex.
Describe the role of golgi tendon organs.
Provide sensory information for a tension response to help prevent over-contraction.
They synapse with inhibitory interneurons of the spinal cord.
Describe:
The two types of muscle reflexes.
- Voluntary: involves conscious thought.
- Involuntary: does not involve conscious thought despite being driven by the nervous system.
There are few ‘purely’ involuntary movements.
List:
TWO key features of ballistic movements.
- Short and rapid.
- Not subject to correction.
(e.g. saccadic eye movements or throwing a ball etc.)
Such movements are typically performed at maximum velocity and acceleration.
List:
TWO key features of guided movements.
- Usually slower.
- Subject to correction.
Note the corrections may be ‘relatively automatic’.