Chapter 11 Flashcards
Produce skeletal movements
Muscle contractions pull on tendons and move bones of the skeleton
Maintain body posture and position
Tension and skeletal muscles maintain body posture
Support soft tissue
Internal organs
Guard entrances and exits
Openings of digestion and urinary tract
Maintenance of body temperature
Heat released by working muscles
Store nutrients
Proteins are broken down and used for energy
Cardiac muscle
- example
- what do cells look like
- Number of nuclei
- are striations present
- voluntary or involuntary
- Heart
- Cells are branched, intercalated discs
- Single nucleus
- Yes
- involuntary
Skeletal muscle
- example
- what do cells look like
- Number of nuclei
- are striations present
- voluntary or involuntary
- Skeletal muscles
- cells are very long and cylindrical
- Multinucleated
- yes
- Voluntary muscle
Smooth muscle example -what do cells look like -Number of nuclei -are striations present -voluntary or involuntary
- Walls of blood vessels, lining digestive and urinary and reproductive organs
- cells are short and spindle-shaped
- Single nucleus
- No
- Involuntary muscle
Arrangement of skeletal muscle cells
- What do they form
- what are the patterns based on
- Four major patterns
Form bundles called fascicles
- Organization of the fascicles
- parallel, convergent, circular, Pennate
Six functions of the muscular system
- Produce skeletal movements
- Maintain body posture and position
- Support soft tissue
- Guard entrances and exits
- Maintenance of body temperature
- Store nutrients
Parallel
- definition
- common?
- contraction
- fascicles are parallel to long axis of the muscle
- most muscles in the body are this type
- muscle shortens and gets larger in diameter
convergent
- definition
- contraction
- fascicles extend over a broad area and converge on one attachment site; very versatile
- contraction of different portions can change direction of pull
circular
- definition
- contraction
- fascicles are arranged as concentric rings/circles around an opening
- contraction causes diameter of opening to decrease
Pennate
- definition
- unipennate
- bipennate
- multipennate
- contraction
- fascicles form a common angle with tendon
- all fascicles are on same side
- fascicles are on 2 sides
- tendon branches
- cannot move tendon as far as parallel muscle but can produce more tension because have more muscle fiber
3 Key principles on how muscles produce movement
- Muscles produce movement by pulling on bones
- Muscles operate as part of a lever system
- Muscles work in groups rather than individually
Muscles produce movement by pulling on bones
-attachment sites
origin and insertion
origin
place where fixed end attaches to a bone, cartilage or connective tissue
insertion
site where movable end attaches
what happens to the origin and insertion during contraction
muscle contraction causes muscle to shorten and moves the insertion toward the origin
lever
- definition
- when does a lever move
- rigid structure that moves on a fixed point called the fulcrum
- when the applied force is sufficient to overcome the resistance
- lever
- fulcrum
- applied force
- load
- bone
- joint
- muscle
- weight of an object held, weight of a limb or weight of the entire body
3 classes of levers
- first class lever
- second class lever
- third class lever
- fulcrum lies between the applied force and the load
- load is located between the applied force and the fulcrum (least common class)
- force is applied between the load and fulcrum (most common class)
3 roles of the muscles
- agonist
- antagonist
- synergist
agonist
- prime mover
- muscle whose contraction is chiefly responsible for producing a particular movement
antagonist
muscle who action opposes that of a particular agonist
Synergist
- helps a larger agonist work more efficiently
- may provide additional pull or may stabilize the origin
how muscles are named (examples)
- direction of muscle fibers
- location
- position
- shape
- size
- origin and insertion
- number of origins
- action
- oblique, rectus
- abdominus, brachialis, femoris
- lateralis, interus, exterus
- deltoid, orbicularis, trapezuis
- longus, magnus
- sternocleidomastoid
- biceps, triceps, quadriceps
- adductor
5 muscles of the head
- frontalis
- Orbicularis oris
- temporalis
- Sternocleidomastoid
- masseter
Frontalis
- origin
- insertion
- action
- aponeurosis
- galea aponeurotica
- skin of forehead
- wrinkles forehead and elevates eyebrows
- flattened tendon
Orbicularis oris
- origin
- insertion
- action
- what is it known as
- mandible and maxillary via muscle fibers surrounding lips
- lips
- closes and presses lips against teeth; protrudes lips during speech and kissing
- kissing muscle
Temporalis
- origin
- insertion
- action
- what is it known as
- temporal bone
- mandible
- muscle of mastication; elevates mandible
- chewing muscle
Sternocleidomasseter
- 2 origins
- insertion
- 2 actions (contraction of both, contraction of one)
- manubrium of the sternum and clavicle
- temporal bone (mastoid process)
- flexes the head at the neck
- tilts head toward the shoulder of the contracting muscle and rotates the face to the opposite side
Masseter
- origin
- insertion
- action
- zygomatic arch
- mandible
- muscle of mastication; elevates mandible
- chewing muscle
5 muscles of the upper trunk
- pectoralis major
- deltoid
- external intercostals
- latissimus dorsi
- trapezius
pectoralis major
- 3 origins
- insertion
- 3 actions
- known as
- clavicle, sternum, costal cartilages
- humerus (intertubercular groove)
- flexes, adducts, and rotates humerus medially at shoulder
- hugging muscle
deltoid
- 2 origins
- insertion
- action
- clavicle and scapula
- humerus (deltoid tuberosity)
- abducts humerus at shoulder
external intercostals
- origin
- insertion
- action
- when does contraction occur
- inferior border of upper ribs (outside and in between ribs)
- superior border of lower rib
- muscle of respiration; elevates rib cage in normal inspiration
- during inhalation
Latissimus dorsi
- 4 origins
- insertion
- 3 actions
- known as
- white part
- midline of lower back, lumbodorsal fascia, spinous processes of lower thoracic and lumbar vertebraes, lower ribs
- humerus (intertubercular groove)
- extends, adducts and rotates medially
trapezius
- 4 origins
- 2 insertions
- action
- midline of neck and back: occipital bone, ligamentum nuchae, spinous process of thoracic vertebrae
- clavicle and scapula (acromion and spine)
- several nerves supply different parts of the trapezius providing a variety of possible actions depending on which part is stimulated; extends head; elevates, depresses and rotates scapula; elevates clavicle
supraspinatus
- origin
- insertion
- action
- scapula (posterior surface)
- greater tubercle of humerus
- abduction at the shoulder
Infraspinatus
- origin
- insertion
- action
- scapula (posterior surface)
- greater tubercle of the humerus
- lateral rotation at the shoulder
Teres Minor
- origin
- insertion
- action
- scapula (lateral surface)
- greater tubercle of the humerus
- lateral rotation at the shoulder
Subscapularis
- origin
- insertion
- action
- scapula (anterior surface)
- lesser tubercle of the humerus
- medial rotation at the shoulder
2 abdominal muscles
- external abdominal oblique
2. Rectus abdominus
External abdominal oblique
- origin
- insertion
- 2 actions (Contraction of both,contraction of 1)
- location
- how do fibers run
- lower ribs
- linea alba
- flexes vertebral column
- flexes vertebral column to one side and supports and compresses abdominal viscera
- outside abdomen
- angle
linea alba
fibrous band in the midline of the abdomen
Rectus abdominus
- origin
- 2 insertions
- 2 actions
- divided by
- increase abdominal pressure
- pubis
- sternum (xiphoid process) and costal cartilages of some ribs
- flexes vertebral column; supports and compresses abdominal viscera
- urination deification, vomiting, parturition (child birth)
3 Anterior arm muscles
- biceps brachii
- brachialis
- brachioradialis
Biceps brachii
- origin (short head, long head)
- insertion
- action
- scapula (coracoid process); scapula (tubercle above glenoid cavity)
- radius
- flexes, elbow and shoulder; supinates forearm
Brachialis
- origin
- insertion
- action
- compare to brachii
- arises from
- anterior humerus
- ulna
- flexes elbow
- deep
- arises directly from periosteum
Brachioradialis
- origin
- insertion
- action
- humerus (lateral epicondyle)
- Radius (near styloid process)
- flexes elbow and forearm
1 Posterior arm muscle
triceps brachii
triceps brachii
- 3 origins
- insertion
- action
- where does the medial head arise from
- lateral head (lateral humerus); medial head (posterior humerus); long head (scapula -tubercle below glenoid cavity)
- ulna (olecranon process)
- extends elbow and forearm
- from periosteum
4 anterior leg muscles
- Sartiorus
- gracilis
- adductor longus
- adductor magnus
Sartiorus
- origin
- insertion
- action
- example
- illium (anterior superior iliac spine)
- medial tibia
- flexes hip and knee and rotates thigh laterally
- crossing your legs
- longest muscle
Gracilis
- origin
- insertion
- action
- pubis
- medial tibia
- adducts femur and flexes knee (flexion of the leg)
- most medial of thigh muscles
Adductor longus
- origin
- insertion
- action
- pubis
- femur (linea aspera), posterior femur
- adducts and extends thigh
Quadriceps femoris
- definition
- 4 muscles
- largest muscle group
- rectus femoris
- vastus laterlis
- vastus medius
- vastus intermedius
- rectus femoris
rectus femoris
- origin
- common tendon
- where does the tendon insert
- action
- illium (anterior inferior iliac spine)
- patellar ligament
- tibia (tibial tuberosity)
- extends knee, flexes hip (extends leg and flexion of thigh, ONLY one that crosses the hip joint)
Vastus lateralis -origin -common tendon where does the tendon insert -action
- femur (greater trochanter)
- patellar ligament
- tibia (tibial tuberosity)
- extends knee (extension of leg)
vastus medius -origin -common tendon where does the tendon insert -action
- femur (linea aspera)
- patellar ligament
- tibia (tibial tuberosity)
- extends knee (leg)
vastus intermedius -origin -common tendon where does the tendon insert -action -arises from
- femur (anterior and lateral aspects)
- patellar ligament
- tibia (tibial tuberosity)
- extends knee (leg)
- periosteum
Tibialis Anterior
- origin
- 2 insertions
- action
- tibia (lateral condyle and shaft)
- tarsal and metatarsal
- dorsiflexes and inverts foot
Shin splints
stress factors of the tibia, inflamation of periosteum, tendonitis of anterior leg
7 posterior leg muscles
- Gluteus maximus
- gluteus medius
- biceps femoris
- semitendinosus
- Semimembranosus
- Gastrocnemius
- Soleus
Gluteus maximus
- 3 origins
- 2 insertions
- action
- pelvis (illium, sacrum, coccyx) and lumbodorsal fascia
- iliotibial tract and femur
- extends and rotates femur laterally (extension and rotation at hip)
iliotibial tract
fibrous band on the surface of the leg that inserts on lateral tibia
Gluteus medius
- origin
- insertion
- action
- preffered site for what
- illium (lateral surface)
- femur (greater trochanter)
- abducts and medially rotates thigh
- intramuscular injections
Biceps femoris
- origin (long head, short head)
- 2 insertions
- action
- ishium (ishial tuberosity); femur (linea aspera)
- fibula (head) and tibia (lateral condyle)
- flexes the knee and extends the thigh (flexion of the leg)
Semitendinosus
- origin
- insertion
- action
- Ishium (ishial tuberosity)
- medial tibia
- flexes knee (leg)
Semimembranosus
- origin
- insertion
- action
- ishium (ishial tuberosity)
- tibia (medial condyle)
- flexes knee (leg)
gastrocnemius
- origin
- insertion
- action
- femur (lateral and medial condyles)
- achilles tendon to calcaneous
- plantar flexes and inverts foot; flexes knee
Soleus
- 2 origins
- insertion
- action
- fibula (head) and tibia (medial)
- achilles tendon to calcaneous
- plantar flexes and inverts foot but does not dross knee