Muscular System Lab Review - Unit 4

Flashcards detailing muscles and their specific actions as defined for the Unit 4 lab biology exam, covering the head, trunk, and limb regions.

Frontalis

Elevate the eyebrows

Temporalis

Elevate the mandible

Zygomaticus

Elevate the corners of the mouth

Orbicularis oculi

close the eye

Orbicularis oris

close the mouth

Masseter

elevate the mandible

Sternocleidomastoid

Used in active breathing, rotate the head, flex the head

Rectus abdominis

Flex the vertebral column, compress the abdomen

Rectus sheath

connective tissue that encases the rectus abdominis

Linea alba

a band of connective tissue that runs from the xiphoid process to the pubic symphysis

External oblique

Flex the vertebral column, rotate the vertebral column, laterally flex the vertebral column, compress the abdomen

Serratus anterior

Protract the scapula

Pectoralis major

Flex and extend the arm, adduct the arm

Trapezius

Elevate and depress the scapula, retract the scapula

Latissimus dorsi

Extend the arm, adduct the arm

Deltoid

Flex and extend the arm, abduct the arm

Supraspinatus

Abduct the arm

Infraspinatus

Laterally rotate the arm

Teres minor

Laterally rotate the arm

Teres major

Extend the arm, adduct the arm

Subscapularis

Medially rotate the arm

Biceps brachii

flex the arm, flex the forearm, supinate the forearm

Brachialis

flex the forearm

Coracobrachialis

flex the arm, adduct the arm

Brachioradialis

flex the forearm

Triceps brachii

extend the arm, extend the forearm

Pronator teres

pronate the forearm

Flexor carpi radialis

flex the hand, abduct the hand

Palmaris longus

flex the hand

Flexor carpi ulnaris

flex the hand, adduct the hand

Extensor carpi radialis longus

extend the hand, abduct the hand

Extensor carpi radialis brevis

extend the hand, abduct the hand

Extensor digitorum

Extend digits

Extensor digiti minimi

extend the $5^{th}$ digit (pinky)

Extensor carpi ulnaris

extend the hand, adduct the hand

Tensor fasciae latae

Flex the thigh, abduct the thigh

Iliotibial tract

band of connective tissue that encases the tensor fasciae latae

Sartorius

Flex the thigh, flex the lower leg

Rectus femoris

Flex the thigh, extend the lower leg

Vastus lateralis

extend the lower leg

Vastus medialis

extend the lower leg

Vastus intermedius

extend the lower leg

Iliopsoas

Flex the thigh

Adductor longus

Adduct the thigh

Gracilis

Adduct the thigh, flex the lower leg

Gluteus maximus

Extend the thigh, abduct the thigh, laterally rotate the thigh

Adductor magnus

Extend the thigh, adduct the thigh

Biceps femoris

Extend the thigh, flex the lower leg

Semitendinosus

Extend the thigh, flex the lower leg

Semimembranosus

Extend the thigh, flex the lower leg

Gastrocnemius

Plantar flex the foot

Soleus

Plantar flex the foot

Calcaneal (Achilles) tendon

connective tissue attaching the gastrocnemius and soleus to the calcaneus

Peroneus

Plantar flex the foot, evert the foot

Extensor digitorum longus

Dorsiflex the foot

Tibialis anterior

Dorsiflex the foot, invert the foot

Flexor digitorum longus

Plantar flexes the foot, flexes the phalanges

muscle tissue

One of the four primary tissue types of the body.

Three types of muscle tissue

Skeletal muscle, cardiac muscle, and smooth muscle.

Skeletal muscle

Voluntary, striated muscle attached to bones; depends completely on the nervous system.

Smooth muscle

Involuntary, nonstriated muscle found in blood vessels, organs, and internal passageway

Cardiac muscle

Involuntary, striated muscle found only in the heart.

Excitability

Ability of muscle cells to respond to a stimulus by generating an action potential.

Action potential

Electrical signal that travels along the muscle cell membrane.

Contractility

Ability of muscle tissue to shorten and produce force.

Extensibility

Ability of muscle tissue to stretch.

Elasticity

Ability of muscle tissue to return to its original length after stretching.

Actin

Protein pulled by myosin during muscle contraction.

Myosin

Protein that pulls on actin to shorten muscle fibers.

Calcium (Ca2+)

Required for muscle contraction in all muscle types

Calcium in skeletal and cardiac muscle

Exposes actin-binding sites by interacting with troponin and tropomyosin.

Calcium in smooth muscle

Activates enzymes that activate myosin heads.

ATP (adenosine triphosphate)

Provides the energy required for muscle contraction.

Muscle relaxation

Occurs when calcium is removed and actin-binding sites are covered again.

Striated muscle

Skeletal and cardiac muscle; has visible stripes due to organized actin and myosin.

Striations

Visible stripes caused by the regular arrangement of actin and myosin.

Nonstriated muscle

Smooth muscle because actin and myosin are not arranged in regular patterns.

Skeletal muscle fibers

Multinucleated muscle cells.

Cardiac muscle fibers

Muscle cells with one or two nuclei.

Smooth muscle fibers

Muscle cells with one nucleus.

Syncytium

Cardiac muscle cells connected so the heart contracts as one unit.

Troponin

Protein that helps regulate muscle contraction by exposing actin-binding sites when calcium bi

Tropomyosin

Protein that blocks actin-binding sites until calcium is present

Location of skeletal muscle

Attached to bones.

Location of cardiac muscle

Heart.

Location of smooth muscle

Blood vessels, skin, visceral organs, and internal passageways.

Function of smooth muscle in arteries

Regulates blood pressure.

Function of smooth muscle in organs

Moves materials through the body.

Muscle fibers

Another name for muscle cells.

Functions of skeletal muscle

Produces movement, maintains posture, stabilizes joints, controls openings, protects organs, and generates heat.

Heat production

Muscle contractions break down ATP, releasing heat.

Skeletal muscle

Voluntary, striated muscle attached to bones

Epimysium

Outer layer of connective tissue surrounding the entire muscle.

Perimysium

Connective tissue surrounding a fascicle.

Endomysium

Connective tissue surrounding an individual muscle fiber.

Fascicle

Bundle of muscle fibers.

Tendon

Connects muscle to bone.

Aponeurosis

Broad, flat tendon-like sheet of connective tissue.

Muscle fiber

A skeletal muscle cell; long, cylindrical, and multinucleated.

Sarcolemma

Plasma membrane of a muscle fiber.