Muscles And nerves Flashcards
Frontalis
Raises eyebrows and wrinkles for head
Obicularis oculi
Closes Eye
obicularis oris
Closes lips; kissing and whistling
Sternocleidomastoid
Flexes, tilts, and rotates head
Zygomaticus
Raises corners of mouth; smiling
Masseter
Elevates (closes) and protracts jaw as when chewing
Trapezius
Shoulder shrugs
Latissimus Dorsi
Extends, adducts, and medially rotates arm
Pectoralis major
Flexes, adducts and medially rotates arm
External oblique
Lateral rotation of the vertebral column; twisting
Rectus abdominis
Flexion of the vertebral column; sit ups
Deltoid
Abducts, flexes, and rotates arm
Triceps brachii
Extends forearm
Biceps brachii
Flexes forearm
Brachioradialis
Flexes arm
Extensor digitorum
Extends fingers and hand
Extensor carpi radialis longus
Extends hand
Flexor carpi ulnaris 
Flexes hand
Palmaris longus
Flexes hand
Tensor fascia latae
Flexes, abducts, and rotates thigh
Adductor longus
Adducts, flexes, and rotates thigh
Gluteus maximus
Extends, abducts, and rotates thigh
Gracilis
Adducts thigh and flexes leg
Sartorius
Crosses the leg
Vastus medialis
Extends leg
Vastus lateralis
Extends leg
Biceps femoris 
Extends thigh and flexes leg
Rectus femoris
Flexes thigh and extends leg
Tibialis anterior
Dorsiflexion of the foot; inverts foot
Fibularis longus
Plantar flexion of the foot; everts foot
Gastrocnemius
Plantar flexion of the foot; flexes leg
What is a motor unit?
A motor neuron and all of the muscle cells it stimulates 
What is meant by recruitment?
The stimulation of additional motor units for increased strength of contraction
Why do some motor units only have a few muscle cells?
To generate precise movements
The constant state of low level tension in a muscle is called
Muscle tone
Muscle twitch
Contraction due to a single stimulus
The three phases of muscle contraction
- Latent period
- Contraction
3. Relaxation
What occurs when a second contraction is added to the first before complete relaxation?
Temporal (wave) summation
What occurs when stimulation is so Rapids at the contraction is smooth and continuous without any relaxation?
Complete (fused) tetanus
What are the three factors that determine the strength of a muscle contraction?
- Frequency of stimulation
- Number of motor units recruited
- Degree of muscle stretch
_________stretched Muscles have the strongest contractions
Moderately stretched
Vestibulocochlear nerve
VIII
Sense of hearing and balance
Glossopharyngeal nerve
IX
Sense of taste, secretion of saliva
Vagus nerve
X
Contraction and relaxation of smooth muscle
Sensory reception of supplied visceral organs
Accessory nerve
XII
Swallowing
Movement of head:
-Sternoclcleiomastoid & Trapezius
muscle
Hypoglossal nerve
XII
Movement of tongue
Olfactory nerve
I
Sense of smell
Optic nerve
II
Sense of vision
Oculomotor nerve
III
Superior, inferior, and medial movement of eye
Trochlear nerve
IV
Movement of eye
Trigeminal nerve
V
Sensation of pain, touch, temperature, chewing
Abducens nerve
VI
Lateral movement of the eye
Facial Nerve
VII
Facial expression,
secretion of saliva and tears,
sense of taste