Exam Review: Bones and Muscles

Lecture Exam 3 Review: Bones and Their Markings, Functions, and Articulations

Major Bones and Markings

Clavicle

Sternal end: The medial end that articulates with the sternum.
Acromial end: The lateral end that articulates with the acromion of the scapula.

Scapula (Shoulder Blade)

Glenoid cavity: The shallow socket that receives the head of the humerus.
Acromion: The bony process on the scapula that forms the highest point of the shoulder.
Coracoid process: A small hook-like structure that provides attachment for ligaments and muscles.
Spine: A prominent ridge on the posterior of the scapula.
Subscapular fossa: The concave surface on the anterior side, providing area's muscle attachment.

Humerus (Upper Arm Bone)

Head of humerus: The rounded proximal end that fits into the glenoid cavity.
Surgical neck: The tapered region distal to the head of the humerus, common site for fractures.
Anatomical neck: The slight constriction below the head of the humerus.
Deltoid tuberosity: The roughened area on the shaft for deltoid muscle attachment.
Trochlea: The groove at the distal end that articulates with the ulna.
Capitulum: The rounded knob on the distal end that articulates with the radius.

Radius (Forearm Bone)

Radial head: The proximal end that articulates with the capitulum of the humerus.
Radial styloid process: The bony prominence at the distal end of the radius.

Ulna (Forearm Bone)

Trochlear notch: The notch that forms a hinge joint with the trochlea of the humerus.
Olecranon: The bony prominence of the elbow.
Ulnar styloid process: The bony prominence at the distal end of the ulna.

Carpals (Wrist Bones)

Total number of carpals: 8.
Know all 8 and their locations: Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, and Hamate.

Metacarpals and Phalanges (Hand)

Metacarpals: The five bones of the hand.
Phalanges: Each finger has three phalanges (proximal, middle, and distal), except the thumb (pollex) which has two.

Coxal Bone (Pelvic Bone)

Ilium: The large, flaring portion.
Ischium: The lower, posterior portion.
Pubis: The anterior portion that joins with the other pubic bone.
Acetabulum: The socket for the head of the femur.
Obturator foramen: The large opening for blood vessels and nerves.
Ischial tuberosities: The bony protrusions that bear weight when sitting.

Femur (Thigh Bone)

Head of femur: The rounded proximal end that articulates with the acetabulum.
Fovea capitis: The small depression in the head for ligament attachment.
Greater trochanter: The large lateral projection for muscle attachment.
Lesser trochanter: The smaller projection on the posterior for muscle attachment.
Medial and lateral condyles: The rounded ends at the distal femur for knee joint articulation.
Medial and lateral epicondyles: Projections above the condyles for ligament attachment.
Patellar surface: The smooth surface that articulates with the patella.

Patella (Kneecap)

A small flat bone that protects the knee joint.

Tibia (Shin Bone)

Tibial tuberosity: The bony prominence where the patellar ligament attaches.
Medial malleolus: The projection on the medial side of the ankle.

Fibula

Head of fibula: The proximal end that articulates with the tibia.
Lateral malleolus: The distal end of the fibula, forming the outer part of the ankle.

Tarsals (Ankle Bones)

Total number of tarsals: 7.
Know all 7 and their locations: Calcaneus, Talus, Navicular, Medial cuneiform, Intermediate cuneiform, Lateral cuneiform, and Cuboid.

Metatarsals and Phalanges (Foot)

Metatarsals: The five bones of the foot.
Phalanges: Each toe has three phalanges (proximal, middle, and distal), except the big toe (hallux) which has two.

Terms and Definitions

Appendicular skeleton: The portion of the skeleton that includes the limbs and girdles.
Sternoclavicular joint: The joint between the sternum and clavicle.
Acromioclavicular joint: The joint between the acromion and the clavicle.
Pectoral girdle: The skeletal structure that supports the arms.
Pelvic girdle: The skeletal structure that supports the legs.
Deltoid muscle: A muscle of the shoulder responsible for arm abduction.
Pubic symphysis: The cartilaginous joint between the two pubic bones.
Hallux: The big toe.
Pollex: The thumb.
Lateral and longitudinal arches: The arch structures of the foot providing support.

Types of Joints

Synarthrosis: Immovable joints.
Amphiarthrosis: Slightly movable joints.
Diarthrosis: Freely movable joints.
Synovial joints: Joints with a fluid-filled cavity.
Synovial fluid: The lubricating fluid secreted by the synovial membrane to reduce friction.

Common Terms in Joint Health

Sprain: Injury to a ligament caused by stretching or tearing.
Meniscus: A C-shaped cartilage in the knee that cushions and stabilizes the joint.
Articular cartilage: Smooth cartilage at the ends of bones to reduce friction.
Fat pads: Soft tissue in the joint providing cushioning.
Bursae: Small fluid-filled sacs that reduce friction between moving parts in joints.
Ligaments: Connective tissue that links bones at joints.
Tendons: Connective tissue that attaches muscle to bone.
Dislocation: When bones in a joint are displaced.
Intracapsular ligament: A ligament located within the joint capsule.
Extracapsular ligament: A ligament located outside the joint capsule.

Movements of Joints

Abduction: Moving a limb away from the body.
Adduction: Moving a limb toward the body.
Circumduction: Movement in a circular pattern.
Flexion: Decreasing the angle between two bones.
Extension: Increasing the angle between two bones.
Plantar flexion: Pointing the toes downward.
Dorsiflexion: Bringing the toes upwards towards the shin.
Pronation: Rotating the forearm so the palm faces downwards.
Supination: Rotating the forearm so the palm faces upwards.
Medial rotation: Rotating towards the midline of the body.
Lateral rotation: Rotating away from the midline of the body.

Types of Joints by Configuration

Gliding joint: Allows sliding movements, like between carpals.
Hinge joint: Allows movement in one plane, like the elbow.
Pivot/rotational joint: Allows rotational movement, like the atlas and axis vertebrae.
Ball and socket joint: Allows for multi-directional movement, like the shoulder and hip joints.

Muscle Types and Structure

Smooth muscle: Involuntary muscle found in walls of hollow organs.
Cardiac muscle: Involuntary muscle found in the heart.
Skeletal muscle: Voluntary muscle attached to bones.

Muscle Contraction Terminology

Contraction: The process of muscle fibers shortening to generate movement.
Fascicle: A bundle of muscle fibers.
Muscle fiber: A single muscle cell.
Epimysium: Connective tissue surrounding the entire muscle.
Perimysium: Connective tissue around each fascicle.
Endomysium: Connective tissue surrounding each muscle fiber.
Myofibril: A rod-like structure in muscle fibers responsible for contraction.
Actin: Thin filament involved in muscle contraction.
Myosin: Thick filament involved in muscle contraction.
Titin: A protein that helps maintain the structure of myofibrils.

Muscle Contraction Mechanisms

Sliding filament theory: Explains how muscles contract by the sliding of actin and myosin filaments past each other.
Sarcomere: The functional unit of a muscle fiber.
Sarcolemma: The cell membrane of a muscle fiber.
Sarcoplasmic reticulum: A structure that stores calcium ions in muscle cells.
Tropomyosin: A regulatory protein that blocks binding sites on actin.
Troponin: A regulatory protein that binds calcium ions and moves tropomyosin away from actin binding sites.
Mitochondria: The powerhouse of the cell, providing ATP for muscle contractions.
T tubules: Tubular extensions of the sarcolemma that help transmit action potentials into the muscle fiber.

Muscle Physiology

Action potential: The electrical signal that triggers muscle contraction.
Neuromuscular junction: The synapse between a motor neuron and a muscle fiber.
Synaptic cleft: The gap between the neuron’s axon terminal and muscle fiber.

Muscle Fiber Characteristics

A band: The dark band in a sarcomere where thick and thin filaments overlap.
I band: The light band in a sarcomere where only thin filaments are present.
Striations: The alternating light and dark bands observed in skeletal muscle fibers.
Z line: The boundary between adjacent sarcomeres.
M line: The center of the sarcomere, where thick filaments are anchored.
Calcium ion (Ca++): An essential ion that enables muscle contraction.
ATP: The energy currency of the cell needed for muscle contraction.
Glycogen: A stored form of glucose used for energy in muscles.

Muscle Conditioning

Acetylcholine (ACh): The neurotransmitter released at the neuromuscular junction to stimulate muscle contraction.
Acetylcholinesterase (AChE): The enzyme that breaks down acetylcholine in the synaptic cleft to terminate the signal.
Motor unit: A single motor neuron and all the muscle fibers it controls.
Slow fibers: Muscle fibers that are fatigue-resistant and used for endurance activities.
Fast fibers: Muscle fibers that contract quickly but fatigue rapidly, suitable for short bursts of power.
Intermediate fibers: Muscle fibers that have characteristics of both slow and fast fibers.

Adaptations of Muscle Tissue

Glycolysis: The metabolic pathway that breaks down glucose for energy, particularly in fast-twitch fibers.
Muscle hypertrophy: The increase in muscle size resulting from resistance training and physical exercise.
Muscle atrophy: The decrease in muscle size due to disuse or disease.