Exam 3: 2. Musculoskeletal System 1

What are the main components of the musculoskeletal system?

Muscles, bones, cartilage, joints, nerves, and blood vessels.

What are the primary functions of the skeletal system?

Support, protection, movement, mineral storage, blood cell production, and energy storage.

What is the difference between origin and insertion in muscle anatomy?

Origin is the fixed attachment (usually proximal), while insertion is the movable attachment (usually distal).

How do muscles function in the lever system?

Bones act as levers, joints as fulcrums, muscles provide effort force, and the load is the resistance.

What are agonist and antagonist muscles?

Agonist (prime mover) muscles perform the primary action, while antagonist muscles oppose that action.

What occurs during muscle contraction?

Muscle contraction occurs when sarcomeres shorten, and muscles pull rather than push.

What is the role of tendons in muscle movement?

Tendons connect muscles to bones, transmit force, and store and release energy during movement.

What are the types of muscle contractions?

Isometric (muscle length does not change), isotonic (muscle length changes), and shunt/stabilizers (pull bones together).

What distinguishes isotonic eccentric contractions?

Isotonic eccentric contractions involve lengthening of the muscle while under tension and are associated with most muscle injuries.

What are the structural classifications of joints?

Fibrous (limited movement), cartilaginous (slight movement), and synovial (free movement).

What are the types of fibrous joints?

Sutures (skull bones) and syndesmosis (joined by dense fibrous connective tissue).

What are the two types of cartilaginous joints?

Synchondrosis (joined by hyaline cartilage) and symphysis (joined by fibrocartilage).

What is the function of synovial fluid?

Lubrication, nourishment of avascular cartilage, and shock absorption.

What are the two specialized cell types in the synovial membrane?

Type A synoviocytes (macrophage-like) and Type B synoviocytes (fibroblast-like).

What is the role of articular cartilage?

It reduces friction between bones and helps in shock absorption.

What is fascia?

A connective tissue network that surrounds muscles and is continuous with tendon connective tissues.

How do muscle shapes relate to their function?

Muscle shapes are named according to their shape, size, attachments, and functions.

What is the significance of motor units in muscle activation?

The number of motor units activated determines the force exerted by the muscle.

What is the difference between shunt muscles and spurt muscles?

Shunt muscles pull bones together, while spurt muscles produce effective movement by contracting obliquely.

What is the importance of understanding muscle attachments?

It helps predict movement rather than relying solely on memorization.