Flashcards in Anatomy 7 - Movement Deck (42)
3 different types of muscle?
Cardiac muscle (involuntary and started)
Smooth muscle (involuntary and non-striated)
Skeletal muscle (voluntary and striated)
What is skeletal muscle made up of?
Skeletal muscle -> fasciles -> muscle fibre (myocyte/ muscle cell) -> myofibrils -> actin and myosin microfilaments
Why does striations look like stripes?
Due to overlapping actin and myosin
What happens when a muscle is strained?
Some of the muscle fibres are torn
Types of skeletal muscles? (5)
Flat with aponeurosis
Example of a circular muscle
Example of a pennate muscle
Example of fusiform muscle
Example of a flat muscle
Example of a quadrate muscle?
What is a flattened tendon called?
What are the 2 points at which muscle attaches to bone called?
(origin is a fixed point where as the insert moves with contraction)
How many origins and insertions does biceps brachi have?
Along which axis does a muscle contract?
Which joints can biceps brachii move?
Radioulnar joint(as spans all 3 of these joints)
What is a reflex?
A rapid, predictable, involuntary reaction to "danger"
What are the 2 main reflexes involving skeletal muscles?
Stretch reflex (deep tendon reflexes)
Flexion withdrawal reflex (sudden flexion to withdraw when we touch something potentially dangerous)
What is an example of a stretch (deep tend reflex)?
Biceps jerk, knee jerk
How are deep tendon (stretch) reflexes tested?
Tendon hammer is used to apply a brief, sudden stretch to the muscle via its tendonIn order to prevent overstitching, the muscle contracts, pulling on the tendon and causing a knee jerk
What tendon is being stretched when creating a knee jerk reflex?
The patellar tendon
How does a deep tendon reflex work in terms of nerves?
Sensory nerve from muscle detected stretch and tells spinal cord
Synapse in spinal cord between sensory and motor nerves
Motor nerve from spinal cord passes message to muscle to contract
What is the synapse called where the motor nerve communicates wit the skeletal muscle during a reflex?
What is the name of the whole route taken by the action potentials during a reflex?
What does a normal stretch reflex indicate is working? (5)
The muscles sensory nerve fibres
motor nerve fibres
The spinal cord connection between the 2
The neuromuscular junction
"descending controls" from the brain
What is the brains role in a reflex?
To prevent the reflex from being overly brisk
What is wrong with a muscle that does not have a functioning motor nerve supply?
It is paralysed
What is paralysed muscle unable to do?
What will a paralysed muscle look like on examination?
What is the word used to describe a muscle that has an intact and functioning motor nerve but the descending controls from the brain aren't working?