Muscular System Mrs. Bruening Flashcards
Muscular System
Responsible for movement. It is made of three types of
muscles – skeletal, smooth and cardiac.
Skeletal muscles
Usually attached to bone and are responsible for voluntary movements. When these muscles contract, they move the bones they are attached to.
Smooth muscles
Found in structures such as the stomach, blood vessels and intestines. These muscles are usually not under voluntary control and are responsible for moving substances throughout the body.
Cardiac muscle
Found only in the heart and is special because it is adapted to be highly resistant to fatigue. This muscle is not under voluntary control.
temporalis
Located on the side of head behind the eyes. It covers the temples and helps open and close the jaw.
masseter
Also helps open and close the jaw. It is located on the side of the face and connects to the mandible.
orbicularis oculi
Surrounds the eye. It is responsible for closing the eye and is the only muscle capable of doing so.
frontalis
Located on the forehead and when it contracts it raises the eyebrows.
nasalis
Located around the nose. This muscle allows you to flare your nostrils.
orbicularis oris
The muscle around the mouth. This muscle closes the
mouth and puckers the lips when it contracts.
mentalis
Is the chin muscle and is sometimes called the pouting muscle because it raises and pushes up the lower lip.
sternocleidomastoid
Passes across the side of the neck and attaches behind the ear on the skull and at the top of the sternum. It is responsible for flexing and extending the neck.
trapezius
Attaches to the back of the head. It is a large muscle that extends from the base of the skull to the lower vertebrae and out to the scapula. It moves the scapulae and supports the arm.
pectoralis major
Found on the chest of the human body. It makes up the majority of the chest muscles and is responsible for moving the shoulder joint in different directions.
latissimus dorsi
Broadest muscle of the back. It is wraps under the armpit to the lower portion of the vertebrae. It is
responsible for adducting, rotating and extending the arm at the shoulder.
external obliques
Large muscles that are situated anterior and lateral to
the abdomen. They extend from the ribs to the pelvis and function to pull the chest downward and compress the abdominal cavity.
rectus abdominus
A paired muscle running vertically on each side of the
anterior wall of the abdomen. This muscle is important to maintaining posture. It also assists with breathing when forcefully exhaling and creating intraabdominal pressure during exercising, defecation and childbirth.
deltoid
Forms the rounded contour of the shoulder. It is responsible for abducting the arm, moving the arm away from the middle of the body.
biceps
Lies on the upper arm between the shoulder and elbow. It is responsible for flexing the elbow.
triceps
Located on the back of the upper limb and is responsible for extending the elbow.
brachioradialis
Located on the forearm but is attached to both the
upper and lower arm. It is responsible for flexing the forearm at the elbow.
extensor muscles of the hand
Extrinsic muscles, meaning they are located outside the hand. These muscles extend, or open flat, the joints of the hand.
flexor muscles of the hand
This group of muscles is found on the underside of the forearm and functions to flex, or bend, the fingers.
gluteus maximus
Attaches to the pelvis and sacrum. It also connects to the illiotibial band.
illiotibial band
Extends down the thigh. The gluteus maximus muscle extends the thigh and supports the trunk of the body.
quadriceps
A group of 4 muscles on the front of the thigh. These
muscles extend the knee and are crucial to walking, running and jumping.
hamstrings
A group of 4 posterior thigh muscles. They extend the hip and flex the knee.
gastrocnemius
Posterior to the soleus. Help to flex the foot and are
important to walking, running and dancing.
soleus
Ahead of the gastrocnemius. Help to flex the foot and are important to walking, running and dancing. maintains posture – the body would fall forward if not for its constant pull.
Achilles tendon
Connects to the heel bone and the calf muscles (soleus and gastrocnemius).
tibialis anterior
Located on the front of the lower leg. It brings the top of the foot closer to the shin.
extensor muscles of the foot
A group of muscles found on the upper surface of the foot that helps to extend, or straighten, the toes. Bands of connective tissue called the superior and inferior extensor retinaculum hold down these muscles.
superior extensor retinaculum
Crosses the lateral side (outside part) of the lower leg.
inferior extensor retinaculum
Crosses the front of the ankle joint.