Joints and Muscles Quiz

Joints and Muscles

• Joints connect bones, enabling movement
• Muscles enable movement by contracting and pulling on bones
• Joints are classified by their movement ability, which includes fibrous, cartilaginous, and synovial joints

Fibrous Joints

• These joints offer no movement between bones
• Examples are sutures in the skull and syndesmoses between the tibia and fibula

Cartilaginous Joints

• Two bones are connected by cartilage
• Cartilage allows limited movement
• Examples are pubic symphysis and intervertebral discs

Synovial Joints

• These joints have a movable capsule
• Synovial fluid lubricates the joint and reduces friction
• Examples are ball-and-socket, hinge, pivot types
• Synovial joints are further categorized by their shape (e.g., ball-and-socket, hinge)

Anatomical Axes

• Sagittal axis: Extends from front to back, important for abduction/adduction
• Vertical axis: Extends from top to bottom, important for internal/external rotation
• Frontal axis: Extends from left to right, and is important for flexion/extension movements

Angular Movements

• Flexion: Decreasing the angle between bones
• Extension: Increasing the angle between bones
• Hyperextension: Extending beyond the normal anatomical position

Abduction/Adduction

• Abduction: Movement away from the midline
• Adduction: Movement toward the midline

Rotation

• Rotation: Movement around a longitudinal axis
• Medial rotation (inward) and lateral rotation (outward) are types

Pronation/Supination

• Supination: External rotation of the forearm
• Pronation: Internal rotation of the forearm

Inversion/Eversion

• Inversion: Sole of the foot faces medially
• Eversion: Sole of the foot faces laterally

General Terms Related to Muscles

• Myology: Study of muscles
• Myocytus: Muscle fiber (cell)
• Muscles are related to movement and are attached to bones
• Types of muscles are skeletal, cardiac, and smooth

Function of Skeletal Muscles

• Movement, heat generation
• Maintaining posture, stabilizing bones and organs

Terminology About Muscles

• Tendon: Attaches muscle to bone
• Aponeurosis: Flat sheet-like attachment to bone
• Contraction (isometric/isotonic): Changes in muscle length

Motor Unit

• A motor neuron and all muscle cells it innervates form a motor unit
• Not all motor units need to contract during muscle contraction

Naming Muscles

• Muscles are named based on their shape, location, number of heads, and size. Examples include pectoralis major, deltoideus, biceps brachii, triceps brachii, iliopsoas, gluteus maximus, gluteus medius, quadriceps femoris, hamstring group.

Mechanical Contraction Mechanism in Skeletal Muscles

• Origin: the starting point of the muscle.
• Insertion: the ending point of the muscle.
• Function: the joint the muscle moves/stabilizes
• Innervation: the nerve that stimulates the muscle.

Shoulder Girdle Muscles

• Deltoid: The muscle that rounds the shoulder
• It controls abduction and adduction of the shoulder and extension and flexion of the upper arm

Brachial Region Muscles

• Biceps brachii: Causes flexion and supination of the forearm (two separate heads)
• Triceps brachii: Extends the forearm (three separate heads)

Hip Region Muscles

• Iliopsoas: Flexors of the thigh (2 muscles)

Gluteal Muscles

• Gluteus maximus: Creates the hip swell; strongest thigh extensor.
• Gluteus medius: Important for hip abduction

Femoral Region Muscles

• Quadriceps femoris: Extension of the knee; important for thigh extension

Crural Region Muscles

• Tibialis anterior: Dorsiflexes the ankle
• Triceps surae: Plantar flexes the ankle (group of muscles)

Thoracic Region Muscles

• Pectoralis major: Adducts the arm
• Serratus anterior: Pulls and rotates scapula

Abdominal Muscles

• Abdominal muscles: Involved in respiration, stabilization, and movements.

Facial Muscles

• Facial muscles control facial expressions
• Innervated by facial nerve (CN VII)

Test your knowledge on the types of joints and muscles. This quiz covers fibrous, cartilaginous, and synovial joints, along with their functions and characteristics. Enhance your understanding of how these structures work together to facilitate movement.