A&P I: Chapter 9 & 10 Exam
Synergist
a group of muscles that work together to cause a movement
Isometric contraction
a muscle produces an increasing tension as the length remains constant
Isotonic contraction
a muscle produces constant tension during contraction
Eccentric contraction
a muscle produces tension, but the length of the muscle is increasing
Antagonist
a muscle working in opposition to agonist
Tetanus
action potential frequency is high enough that no relaxation of muscle fibers occurs
Tendon
attaches muscle to bone
Myofilaments
contains actin and myosin
Pectoralis minor
depresses scapula and elevates ribs
Contracting the trapezius muscle would
extend and laterally flex the neck.
Triceps brachii
extends forearm at elbow/insertion of ulna
Teres major and teres minor aren't involved in
flexion and abduction of the arm
The muscles of the anterior group of forearm muscles are primarily
flexors
Tropinin
has a calcium-binding site
Rectus abdominis
has its origin at the pubic crest and symphysis pubis
Shivering
helps raise body temperature
Transversus abdominis
inserts on the diploid process and the line alba
Muscle tone
is a constant tension produced by muscles for long periods of time
Muscle atrophy
is characterized by a decrease in muscle size
Complete tetanus
is the condition in which stimuli occur so rapidly that there are no intervening relaxations
Incomplete tetanus
is the condition in which the muscle fiber only partially relaxes between contractions
Belly
largest portion of the muscle between origin and insertion
The arm is attached to the thorax by the
latissimus dorsi and pectoralis major
Pelvic diaphragm is formed by the
levator ani and coccygeus muscles
The length of the resting sarcomere is
longer than the length of a contracted sarcomere.
Agonist
muscle that, when it contracts, causes an action
Action potentials
occurs when the local potentials reaches threshold levels
Quadratus lumborum
originates on the iliac crest and lower lumbar vertebrae
Flexion of the hip is a movement produced by the
psoas major and iliacus
Body temperature
results from the heat produced when muscles contract.
Contracting the right sternocleidomastoid muscle would
rotate the head towards the left
Serratus anterior
rotates and protracts scapula, and elevates the ribs
Infraspinatus
rotates arm laterally
Fixators
stabilize the origin of the prime mover
Cross-bridge
the combination myosin heads with active sites on actin molecules
Power stroke
the movement of a myosin head while attached to actin myofilament
Concentric contractions
the muscle produces increasing tension as it shortens
Insertion
the muscle that does most of the movement
Prime movers
the muscle that does most of the movement
Origin
the stationary end of the muscle
Class I Levers
1.) Fulcrum between force and weight 2.) Seesaw 3.) Head movement at the atlantoccipital joint
Class III Levers
1.) Pull located between fulcrum and weight 2.) Person using a shovel 3.) Most common: biceps brachia with below as fulcrum
Class II Levers
1.) Weight is between fulcrum and pull 2.) Wheelbarrow 3.) Standing on toes; metatarsophalangeal joint
Aponeurosis
A broad, flat tendon
Tropomyosin
A protein found along the groove of the F-actin double helix
