AP1 Lab 11 Muscles

This set of flashcards covers the key vocabulary and concepts related to muscles as discussed in the AP1 Lab 11 lecture.

Cardiac muscle cell

A type of muscle tissue found in the heart, characterized by intercalated discs and involuntary control.

Skeletal muscle cell

A type of muscle tissue that is striated and under voluntary control, responsible for movement of the skeleton.

Smooth muscle cell

A type of muscle tissue that is non-striated and involuntary, found in the walls of hollow organs.

Motor Unit

A motor neuron and the skeletal muscle fibers it innervates, crucial for muscle contraction.

Epicranius

A muscle with two parts (frontal and occipital bellies) that covers the upper part of the skull.

Zygomaticus major

A facial muscle that helps elevate the corners of the mouth for smiling.

Orbicularis oculi

A circular muscle around the eye responsible for closing the eyelids.

Platysma

A superficial muscle that covers the neck and lower face, important in facial expressions.

Deltoid

The shoulder muscle responsible for arm abduction and flexion.

Biceps brachii

A muscle located in the upper arm that flexes the elbow and supinates the forearm.

Gastrocnemius

The main calf muscle, responsible for plantar flexion of the foot and flexion of the knee.

Achilles tendon

The tendon that connects the calf muscles to the heel bone, critical for walking and running.

Tibialis anterior

A muscle located in the front of the lower leg, responsible for dorsiflexion of the foot.

Extensor digitorum

A muscle that extends the fingers and toes, located in the forearm and lower leg.

Flexor carpi radialis

A muscle that flexes the wrist and abducts the hand.

Latissimus dorsi

A large back muscle that extends, adducts, and medially rotates the arm.

Infraspinatus

A muscle located on the back of the shoulder, involved in externally rotating the arm.

Sartorius

The longest muscle in the human body, it helps flex, abduct, and laterally rotate the thigh.

Adductor muscles

A group of muscles in the thigh that adduct the leg towards the body midline.

Fascicle

A bundle of skeletal muscle fibers surrounded by perimysium.

Epimysium

The outer layer of connective tissue that surrounds an entire muscle.

Perimysium

The connective tissue that surrounds individual fascicles within a muscle.

Endomysium

The delicate connective tissue that surrounds individual muscle fibers.

Sarcomere

The basic contractile unit of muscle tissue, consisting of repeating units of actin and myosin.