CH # 8: Muscular System Flashcards
A neurotransmitter at the neuromuscular junction
Acetylcholine
An enzyme that inactivates acetylcholine
Acetylcholinesterase
A broad flat sheet of connective tissue that connects 1 muscle 2 another
Aponeurosis
The ability of tissue 2 return 2 its original shape after contraction or extension
Elasticity
Fibrous connective tissue that surrounds a whole muscle
Provides a passage way 4 blood vessels and nerves
Supports and protects the contained muscle 2 w/stand the forces of contraction
Epimysium
2 names 4 the ability of muscle and nerve tissue 2 recieve and respond 2 stimuli
Excitability
Irritability
The ability of muscle tissue 2 stretched when pulled
Extensibility
The end of a muscle that is attached 2 a relatively moveable part
The end opposite the origin
Insertion
A single neuron and all the muscle fibers it stimulates
Motor unit
2 names 4 the area of communication between the axon terminal of a motor neuron and the sarcolemma of a muscle fiber
Neuromuscular junction
Myoneural junction
A chemical substance that is released at the axon terminals 2 stimulate a muscle fiber contraction or an impulse in another neuron
Neurotransmitter
The end of a muscle that is attached 2 a relatively immovable part
The end opposite the insertion
Origin
2 names 4 the muscle that is mainly responsible 4 a particular body movement
Prime mover
Agonist
The membrane covering of a muscle cell
Sarcolemma
Cytoplasm of a muscle cell
Sarcoplasm
Muscles that support a prime mover but r not capable of producing the movement by themselves
2 or more muscles work together 2 produce a movemet
Synergist
A type of muscle tissue
- location: attached 2 bone
- function: produces body movement
- cell shape: cylindric
- number of nuclei: many
- striations: present
- type of control: voluntary
Skeletal muscles
A type of muscle tissue
- location: walls of internal organs and blood vessels
- function: contraction of viscera and blood vessels
- cell shape: spindle-shaped (tapered ends)
- number of nuclei: 1
- striations: absent
- type of control: involuntary
Visceral muscle tissues
A type of muscle tissue
- location: heart
- function: pumps blood through heart and blood vessels
- cell shape: cylindric and branching
- number of nuclei: 1
- striations: present
- type of control: voluntary
Cardiac muscle tissues
Fulfills 4 important functions:
1) movement
2) posture
3) joint stability
4) heat production
Muscle contractions
Skeletal muscles r stimulated 2 contract by special nerve cells called?
Motor neurons
The name 4 the fluid-filled space between the axon terminal and the sarcolemma
Synaptic cleft (gap)
When a nerve impulse reaches an axon terminal , ACh is released. ACh diffuses across the synaptic cleft and binds w/the receptor sites on the sarcolemma. This causes the microfilaments 2 slide across 1 another resulting in contraction
Sliding filament theory of contraction
A unique high-energy compound that is stored in muscles which provides almost instantaneous regeneration of ATP
Creatine phosphate
These become the primary source 4 muscles that r actively contracting 4 extended periods of time.
Fatty acids and glucose
This process causes fatty acids and glucose 2 b broken down in the mitochondria
Aerobic respirition
This process is when glucose is broken down 2 provide energy 2 muscles that r vigorously contracting 4 long periods of time. This happens because the circulatory system isn’t able 2 deliver enough oxygen 2 muscles
Anaerobic respiration
Muscle name meaning huge
Vastus
Consists of 2 muscles on both sides of the neck
Origin is on the sternum and clavicle-Insertation is on the mastoid process
When these muscles contract together, the neck is flexed and the head is bent towards the chest
When 1 muscle contracts, the head turns toward the direction opposite the side that is contracting
Ex.Left contracts=head turns right
Right contracts=head turns left
Sternocleidomastoid
Means 2 bend
Bringing 2 bone together which decreases the angle between them
Ex. Bending the elbow or the knee
Flexion
Means 2 straighten
It increases the angle between 2 bones
Ex.straightening the elbow or the knee after it has been flexed
Extension
Means 2 take away
2 move a bone or limb away from the midline or axis of the body
Ex. -Outward movement of the legs during jumping jacks
- Moving the arms away from the body - Spreading the fingers apart
Abduction
Means 2 bring together
2 move a bone or limb toward the midline of the body
Ex. -bringing the arms back 2 the sides of the body
-moving the legs back 2 the anatomical position
Adduction
A muscle used 4 facial expression
A sphincter that lies around the eye
Movement causes winking, blinking and squinting
Orbicularis oculi
A muscle of mastication
It is located along the ramus of the mandible and is a synergist of the temporalis
Masseter
Muscles that oppose or reverse a particular movement
Ex. The muscles responsible 4 flexing and straightening the arm at the elbow r described as being this 2 one anotherq
Antagonist muscles
A muscle that is the primary extender of the forearm and the only muscle in the posterior compartment
Triceps brachii
A muscle that is the primary extender of the forearm and located in the anterior muscle compartment
Biceps brachii
Includes 4 muscles on the anterior and lateral side of the thigh. As a group, they r the primary extensors of the leg, straightening at the knee.
Includes 4 muscles:
- vastus lateralis
- vastus intermedius
- vastus medialis
- rectus femoris
Quadriceps femoris