A&P lecture Exam 2 (ch.7)
brachialis and brachioradialis (forearm)
flex elbow
quadratus lumborum (spine)
flex the spinal column and depresses the ribs
flexor carpi ulnaris, flexor carpi radialis and palmaris longus (wrist)
flex wrist
pectoralis major (arm)
flexes arm at the shoulder
biceps brachii (forearm)
flexes elbow and supinates forearm
muscles that move the hand and fingers are located in the _____
forearm **(only tendons cross the wrist)
largest hip flexor is ____ and is composed of _____ and ______
iliopsoas; psoas major; iliacus
tibialis (foot)
inversion & tibialis anterior produces dorsiflexion (flexes ankle & elevates sole)
muscle fatigue is caused by a buildup of ______ & _____ pH
lactic acid; decreases pH
which muscle do you use to shrug your shoulders? and which muscle is the antagonist?
levator scapulae (elevates scapula) Antagonist: subclavius & pectoralis minor (depresses scapula)
erector spinae (spine)
maintain an erect spinal column and head -contain: iliocostalis; longissimus; spinalis
Glucose and fatty acids are catabolized during which muscle activity
moderate muscle activity
synergist muscle
muscle that helps the prime mover work efficiently
antagonist muscle
muscle that opposes a movement by another muscle
looking at the muscle name sternocleidomastoid, you would identify that this muscle is located in the area of the _______
neck (other muscles of neck: stylohyoid, mylohyoid, omohyoid, digastric, platysma)
the first part of the name of a muscle refers to its _____ while the second part of the name refers to its ______
origin; insertion
perineum
pelvic cavity floor formed by broad sheet of muscles that: - support organs of pelvic cavity -flex the coccyx (tailbone) -control movement of material through the anus and urethra
Gastrocnemius & soleus (foot)
plantar flexion (extend ankle & elevate heel)
pronators and supinator
rotate radius
subscapularis, teres major, infraspinatus, and teres minor
rotate the arm
sternocleidomastoid muscle (neck)
rotates head and flexes neck
Individuals who excel at endurance activities such as cycling or long-distance running have a higher than normal percentage of _______ muscle fibers; rely on which metabolism
slow muscle fibers; rely on aerobic metabolism (30 mol of ATP)
mylohyoid muscle (neck)
supports the tongue
platysma (head & neck)
tenses skin of neck and depresses mandible
insertion (muscle)
the end of the muscle that moves when the muscle contracts
origin (muscle)
the end of the muscle that stays stationary
prime mover, or agonist muscle
the muscle that is chiefly responsible for producing a movement
ankle flexors
tibialis anterior
you are lying on the floor with your feet flat and your knees up practicing your abdominal crunches. You raise your upper body to the ceiling, up and down. What muscles are you using to the greatest extent?
transverse abdominus - compresses abdomen
action (muscle)
what happens when the muscle contracts (flexion, extension, adduction or abduction)
splenius capitis and semispinalis capitis (spine)
work together to either extend the head or tilt the head
adductors (thigh) include:
-adductor magnus -adductor brevis -adductor longus -pectineus -gracilis
flexors of the knee that are known as hamstrings:
-biceps femoris -semimembranosus -semitendinosus -sports injury: pulled hamstring
ankle extensors
-gastrocnemius -fibularis longus -soleus -fibularis brevis -tibialis posterior
carpal tunnel syndrome
-inflammation of retinacula tissue (hold tendons in place) causes weakness in the hand muscles - results from repetitive hand or wrist movement
deltoid (arm)
-major abductor of arm -supraspinatus assists at beginning of movement
axial muscles divided into four parts
-muscles of head and neck (facial expressions, swallowing & chewing) -muscles of the spine (flexors and extensors of head, neck and spinal column) -muscles of the trunk (forms muscular walls of the thoracic and abdominopelvic cavities) -muscles of the pelvic floor (extend between sacrum and pelvic girdle forming the muscular perineum, which closes the pelvic outlet)
Extensors of the knee (quadriceps femoris):
-rectus femoris -the three vastus muscles (lateralis, medialis, intermedius)
flexors/not hamstrings (leg) include:
-sartorius: produces lateral rotation at hip -popliteus: unlocks knee joint
which of the following is an effect of aging on the muscular system? -tolerance for exercise increases -skeletal muscles become more elastic -skeletal muscle fibers become smaller in diameter -muscle fibers contain more myoglobin -scar tissue formation does not occur
-skeletal muscle fibers become smaller in diameter **other answers should be: -tolerance for exercise decreases -skeletal muscles become less elastic -muscle fibers contain less myoglobin -scar tissue forms
rotator cuff (arm)
-supraspinatus -infraspinatus -teres minor -subscapularis **common site of sport injury such as muscle strain (tear or break in muscle)
excerise engages multiple systems
1. muscular system -active muscles consume oxygen and generate CO2 and heat 2. cardiovascular system -increases heart rate and speeds up delivery of oxygen 3. respiratory system -increases rate and depth of respiration 4. integumentary system -dilation of blood vessels and sweating combine to increase cooling 5. nervous and endocrine systems -control heart rate, respiratory rate, sweat gland activity, and release of stored energy
four effects of aging on skeletal muscle
1. skeletal muscle fibers become smaller in diameter (less ATP, CP, glycogen, and myoglobin) - # of myofibrils decreases 2. skeletal muscles become less elastic -increasing fibrous tissue (fibrosis) muscles less flexible 3. tolerance for exercise decreases (tire quickly, decrease in thermoregulation) 4. ability to recover from injury is decreased & scar tissue forms
1.a torn calcaneal tendon would affect which of the following movements of the foot? 2.which two muscles share the calcaneal tendon in common?
1.plantar flexion 2.Gastrocnemius & soleus
serratus anterior (pectoral girdle)
abducts (protracts) and rotates scapula
abductor pollicis and extensor pollicis
abducts and extends thumb respectively
rhomboid muscle (pectoral girdle)
adducts (retracts) and rotates scapula laterally
epicranium (scalp) contains occipitofrontalis: anterior _______ & posterior _____
anterior: frontalis muscle; raises eyebrowns and frowns forehead posterior: occipitalis muscle; tenses and retracts scalp
fixator muscles
are synergists that stabilize the origin of a prime mover by preventing movement at another joint
temporalis & pterygoid (mouth)
assist masseter in chewing by elevating mandible
majority of our skeletal muscles are ______ muscles
axial
Why can't heart muscle (unlike skeletal muscle) undergo tetanus?
because the heart has to be able to consistently contract and pump blood in a controlled fashion
in infants, which muscle allows for the mouth to form a tight fit around the nipple during suckling at the breast?
buccinator
external and internal obliques and the transversus abdominis (axial;trunk)
compress abdomen, can flex spine
buccinator (mouth)
compresses cheek when blowing forcefully
orbicularis oris (mouth)
constricts opening of the mouth
pectoralis minor and subclavius (pectoral girdle)
depress and abduct scapula
omohyoid muscle (neck)
depresses larynx and hyoid bone
digastric muscle (neck)
depresses mandible
rectus abdominis (axial;trunk)
depresses ribs, flexes spine
trapezius muscle (pectoral girdle)
diamond shaped; has many actions depending on region
diaphragm (axial;trunk)
dome shaped muscle that expands the thoracic cavity and compresses the abdominopelviccavity
levator scapulae
elevates scapula
stylohyoid muscle (neck)
elevates the larynx
anterior and posterior epicranium are connected by
epicranial aponeurosis
Fibularis (foot)
eversion & plantar flexion
extensor digitorum and flexor digitorum (fingers)
extend and flex fingers respectively
extensor carpi radialis and extensor carpi ulnaris (wrist)
extend wrist
triceps brachii (forearm)
extends elbow
latissimus dorsi
extends the arm at the shoulder
gluteal muscles (thigh)
extension, rotation and abduction at hip joint
digital extensors (toes)
extensor digitorum longus -tendon of extensor hallucis longus
external and internal intercostals (axial;trunk)
externals elevate ribs and internals depress ribs