Muscle Physiology and Joint Functions Review

This set of flashcards covers key vocabulary and concepts related to articulation, muscle physiology, and the nervous system, as discussed in the lecture notes.

Articulation

The point where two bones meet; also known as a joint.

Synarthrosis

A joint with no movement.

Amphiarthrosis

A joint that allows slight movement.

Fibrous Joint

A type of joint connected by connective tissue, allowing very little movement.

Cartilaginous Joint

A joint where the bones are connected by cartilage.

Suture

A type of synarthrotic fibrous joint found in the skull.

Syndesmosis

A type of fibrous joint that allows slight movement, structural classification as fibrous.

Synovial Membrane

A membrane that lines the joint capsule and produces synovial fluid.

Synovial Fluid

Fluid that lubricates joints and reduces friction.

Diarthrotic Joint

A joint that allows free movement.

Joint Capsule

The fibrous tissue surrounding a synovial joint.

Tendon Sheath

A layer of synovial membrane that surrounds a tendon.

Bursa

A fluid-filled sac that reduces friction between moving parts in the body's joints.

Plantar Flexion

Movement that decreases the angle between the foot and the leg, pointing the toes down.

Flexion

Bending movement that decreases the angle between body parts.

Extension

Straightening movement that increases the angle between body parts.

Abduction

Movement of a limb away from the midline of the body.

Adduction

Movement of a limb towards the midline of the body.

Pivot Joint

A joint that allows rotational movement; an example is the neck.

Hinge Joint

A joint that allows bending and straightening; an example is the elbow.

Ball-and-Socket Joint

A joint that allows movement in multiple directions; an example is the shoulder.

Meniscus

A crescent-shaped cartilage structure found in certain joints, particularly the knee.

Gomphosis

A type of fibrous joint that binds the teeth to bony sockets.

Calcium Release Trigger

The process initiated by an action potential leading to muscle contraction.

Myofilaments

The filaments of myofibrils, constructed from proteins, primarily actin and myosin.

Sarcoplasmic Reticulum

A specialized smooth endoplasmic reticulum found in muscle cells, important for calcium storage.

Motor Unit

A motor neuron and the muscle fibers it innervates.

Neuromuscular Junction

The synapse or junction between a motor neuron and a muscle fiber.

Excitatory Neurotransmitter

A neurotransmitter that causes the postsynaptic membrane to become more positive (depolarization).

Inhibitory Neurotransmitter

A neurotransmitter that causes the postsynaptic membrane to become more negative (hyperpolarization).

Acetylcholine

A neurotransmitter used at neuromuscular junctions to stimulate muscle contraction.

Action Potential

A short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls.

Saltatory Conduction

The rapid transmission of an action potential along a myelinated axon.

All-or-None Principle

The principle stating that the strength of a response of a nerve cell is not dependent on the strength of the stimulus.

Muscle Tone

The continuous and passive partial contraction of the muscles.

Recruitment

The process of increasing the number of active motor units in a muscle.

Atrophy

The wasting away or decrease in size of muscle tissue.

Hypertrophy

The increase in muscle size through exercise or increased workload.

Skeletal Muscle Tissue

Striated muscle tissue that is voluntary and under conscious control.

Cardiac Muscle Tissue

Involuntary muscle tissue found only in the heart, with unique intercalated disks.

Smooth Muscle Tissue

Involuntary muscle found in walls of hollow internal organs.

Muscle Fascicle

A bundle of muscle fibers.

Myofibril

A long protein filament found within muscle cells that aids contraction.

Myosin Head

The part of myosin that binds to actin and is involved in muscle contraction.

Troponin

A protein that binds calcium and helps regulate muscle contraction.

Tropomyosin

A protein that lays over actin and blocks the binding sites for myosin.

Neurilemma

The outermost layer of Schwann cells, important for the repair of damaged nerve fibers.

Calcium Pumps

Proteins that transport calcium ions back into the sarcoplasmic reticulum.

Isotonic Contraction

A type of muscle contraction where the muscle changes length while contracting.

Treppe

A phenomenon in which muscle contractions increase in strength with repeated stimulation.