BIOL 2311 UNT EXAM 3

List two of the seven criteria listed in your lab manual that are used to name muscles?

location amd shape

What are the individual contractile units of a muscle cell called?

sarcomeres

If a muscle contracts against a load that is too heavy for the muscle to lift, what type of contraction is the muscle demonstrating?

isometric

A neuron and all of the muscle cells that it stimulates are together called a _________________?

motor unit

If we increase the frequence of stimulation of a muscle untill we acheive a steady sustained contraction, we will have caused what phenomenon?

tetanus

If we stimulate a muscle, and then stimulate it again immediately after it has been allowed to relax, we observe that the second contraction of the muscle is slightly greater than the first. What do we call this phenomenon?

treppe

Define "origin" as it applies to skeletal muscles.

immovable site of attachment

Name one action of the gastrocnemius muscle.

plantar flexion of foot

Name one action of the tibialis anterior muscle.

dorsiflexion of foot

Name one action of the external oblique muscle.

compress abdominal wall

Name one action of the triceps brachii muscle.

extension of forearm

Name one insertion of the brachialis muscle.

coronoid process of ulna

Name one insertion of the external oblique muscle.

linea alba

Name one insertion of the flexor carpi radialis muscle.

base of metacarpals II and III

Name one insertion of the biceps brachii muscle.

radial tuberosity

Name one origin of the vastus medialis muscle.

linea aspera

Name one origin of the tibialis anterior muscle.

tibia

Name one origin of the zygomaticus minor muscle.

zygomatic bone

Name one origin of the rectus abdominis muscle.

pubic crest and symphysis

What do we call the period of time between the application of a stimulus to a muscle and the first observable response or movement of the muscle?

latent phase

A single contraction of a muscle is called a _____________?

twitch

What do we call muscles that aid the action of other muscles by reducing undesirable or unnecessary movement?

synergists

Name one action of the platysma muscle.

depresses mandible

Name one action of the brachialis muscle.

flexion of forearm

Name one action of the biceps brachii muscle.

flexion of forearm

Name one insertion of the trapezius muscle.

clavicle

Name one insertion of the pectoralis major muscle.

intertubercular sulcus of humerus

Name one insertion of the deltoid muscle.

deltoid tuberosity of humerus

Name one insertion of the semimembranosus muscle.

medial condyle of tibia

Name one origin of the semitendinosus muscle.

ischial tuberosity

Name one origin of the infraspinatus muscle.

infraspinous process of scapula

Name one origin of the platysma muscle.

fascia of chest

Name one origin of the rectus femoris muscle.

acetabulum

If we require a muscle to contract until it starts to run out of ATP, what do we call the state of the muscle at that point?

fatigue

Name one action of the semimembanosus muscle.

flexion of leg

Name one action of the semitendinosus muscle.

flexion of leg

Name one insertion of the zygomaticus minor muscle.

skin and muscle at corner of mouth

Name one origin of the gastrocnemius muscle.

medial and lateral condyles of femur

Name one origin of the buccinator muscle.

maxilla

Name one origin of the infraspinatus muscle.

infraspinous process of scapula

Define "insertion" as it applies to skeletal muscles.

movable site of attachment

Name one action of the rectus abdominis muscle.

Flexion and rotation of vertebral column

Name one action of the flexor carpi radialis muscle.

flexion of hand

Name one action of the extensor digitorum muscle.

extension of fingers

Name one insertion of the extensor digitorum muscle.

distal phalanges of fingers 2-5

Name one insertion of the masseter muscle.

angle and ramus of mandible

Name one insertion of the gastrocnemius muscle.

calcaneus

Name one origin of the zygomaticus major muscle.

zygomatic bone

By steadily increasing the number of motor units that are activated, we produce a steady increase in the force produced by a muscle. This process is called __________________?

recruitment

Name one action of the infraspinatus muscle.

lateral rotation of arm

Name one action of the orbicularis oculi muscle.

closes eyelids

Name one action of the vastus medialis muscle.

extension of leg

Name one insertion of the vastus medialis muscle.

patella

Name one insertion of the orbicularis oculi muscle.

eyelid

Name one origin of the supraspinatus muscle.

supraspinous fossa of scapula