Lecture 6: Muscle Anatomy and Physiology

Vocabulary flashcards identifying the primary functions of major human muscles, cell structures, and metabolic processes involved in muscle contraction and movement.

Frontalis

raise eyebrows

Orbicularis oculi

winking

Zygomaticus

smiling

Orbicularis oris

kissing

Temporalis

chewing

Masseter

chewing

Buccinator

whistling

Sternocleidomastoid

flexes head

Intercostal muscles

breathing

Diaphragm

breathing

Rectus abdominus

flexes trunk (body)

External oblique

laterally flexes trunk (body)

Deltoid

abducts arms

Biceps brachii

flexes elbow

Triceps brachii

extends elbow

Pectoralis major

adducts arms

Serratus anterior

punching

Trapezius

extends head

Latissimus dorsi

adducts arms

Gluteus medius

abducts thigh

Gluteus maximus

extends thigh

Gracilis

adducts thigh

Quadriceps

extends knee

Tibialis anterior

dorsiflexion, standing on heels

Hamstrings

flexes knee

Gastrocnemius

plantarflexion, standing on toes

Fascia

tough connective tissue

Tendon

attaches muscles to bones

Aponeuroses

attaches muscles to muscles

Sarco-, myo-

muscle

Sarcolemma

muscle cell membrane

Sarcoplasmic reticulum (SR)

stores and releases calcium

Muscle proteins

actin, myosin, troponin, tropomyosin

Motor neurons

send electricity, release ACh onto muscle cells

Acetylcholine (ACh)

neurotransmitter released from neurons

Acetylcholinesterase (AChase)

breaks down ACh, relaxes muscles

Creatine phosphate

quick burst of ATP

Aerobic respiration

generates energy with oxygen, waste $CO_2$

Anaerobic respiration

generates energy without oxygen, waste lactic acid

Antagonist muscles

perform opposite actions

Agonist muscles

perform the same actions

Hypertrophy

increase size of muscle cells

Atrophy

decrease size of muscle cells