Muscular system Flashcards
What muscles are on the wrists?
wrist flexors
Wrist extensors
What muscles are on the elbow?
Bicep Brachii & Tricep Brachii
What muscles are on the Shoulder?
Deltoid
- Latissimus dorsi
- Pectoralis major
What muscles are on the Spine?
Rectus abdominals
Erector spinae group
External obliques
Internal obliques
What muscles are on the Hip?
illiopsoas
Glueteus maximus
Gluteus medius & minimus
Adductor group
What muscles are on the Knee?
hamstrings
Semitendinosus
Bicep femoris
What muscles are on the Ankle?
Tibialis anterior
- Gastrocnemius - Soleus
What is the Origin?
Point of attachment of a muscle that remains fixed during muscle contraction
What is Antagonistic muscle action?
As one muscle shortens to produce movement the other muscle lengthens
What is Agonist muscle?
What is Antagonist muscle?
The muscle responsible for movement at a joint
The muscle that has an action opposite to that of the agonist
What is a Fixator?
A muscle that stabilises one part of the body whilst another causes movement.
E.g. The rotator cuff muscles are the ‘fixator’ during a bicep curl.
Describe the sagittal plane
The sagittal plane is a vertical plane that divides the body into right and left sides.
Describe the frontal plane
The frontal plane is also a vertical plane but this divides the body into front (anterior) and back (posterior).
Describe the transverse plane
The transverse plane is a horizontal plane that divides the body into upper (superior) and lower (inferior) halves.
What is adduction and abduction?
Adduction- Movement towards the midline of the body
Abduction- Movement away the midline of the body ‘abduct’
What is circumduction?
Circumduction- A movement of a body part that outlines a cone. It consists of a combination of flexion, extension, adduction, and abduction.
How do muscles contract?
A skeletal muscles (muscles attached to the skeleton) can only contract when stimulated by an electrical impulse sent from the Central Nervous System (CNS).
What does the Cerebellum control?
Controls all of our muscle contractions
How does a motor unit work?
1) Cell generates and impulse
2) Impulse pass down the neuron
3) Impulse arrives at motor end plates
4) Muscle fibres contract
What has to be big enough and above threshold for a muscular contraction to be created?
If action potential is big enough and the electrical charge is above threshold, a muscle contraction is created.
How do you create a muscle contraction?
Impulse sent by the cell body in the cerebellum
Action potential (Impulse) sent down the neuron/nerve to the motor end plates
Neurotransmitter called Acetylcholine flows into the synaptic Cleft
If action potential is big enough and the electrical charge is above threshold, a muscle contraction is created.
This happens in an ‘all or none’ law
What is the All or None Law?
If the action potential does not reach the threshold charge, NONE of the muscle fibres will contract
