Chapter 6: Bones and Skeletal Tissue

Overview of Skeletal Tissues

The skeletal system is composed of bones and cartilage, which provide structure, protection, and facilitate movement. Understanding the types and functions of skeletal tissues is fundamental to anatomy and physiology.

• Types of Skeletal Tissues:

  • Bone: Rigid tissue providing support and protection.

  • Cartilage: Flexible tissue found in joints, ear, nose, and other areas.

• Functions of Skeletal Tissues:

  • Support for the body

  • Protection of internal organs

  • Facilitation of movement

  • Mineral storage (e.g., calcium, phosphate)

  • Blood cell production (hematopoiesis)

• Types of Cartilage:

  • Hyaline cartilage: Most abundant, found in joints, ribs, nose.

  • Elastic cartilage: Flexible, found in ear and epiglottis.

  • Fibrocartilage: Tough, found in intervertebral discs and pubic symphysis.

• Bone Structure:

  • Compact bone: Dense, provides strength.

  • Spongy bone: Porous, contains red marrow.

• Bone Cells:

  • Osteoblasts: Build bone.

  • Osteoclasts: Break down bone.

  • Osteocytes: Maintain bone tissue.

Bone Growth and Remodeling

Bones grow and remodel throughout life, adapting to stress and repairing damage.

• Ossification: Process of bone formation.

• Remodeling: Continuous process of bone resorption and formation.

• Hormonal Regulation: Parathyroid hormone and calcitonin regulate calcium levels.

Chapter 7: The Skeleton

Axial and Appendicular Skeleton

The skeleton is divided into two main parts: axial and appendicular. Each has distinct bones and functions.

• Axial Skeleton:

  • Skull, vertebral column, rib cage

  • Protects brain, spinal cord, and thoracic organs

• Appendicular Skeleton:

  • Limbs and girdles (shoulder and pelvic)

  • Facilitates movement

• Major Bones:

  • Skull: Cranial and facial bones

  • Vertebral column: Cervical, thoracic, lumbar, sacrum, coccyx

  • Thoracic cage: Ribs and sternum

  • Upper limb: Humerus, radius, ulna, carpals, metacarpals, phalanges

  • Lower limb: Femur, tibia, fibula, tarsals, metatarsals, phalanges

Chapter 8: Joints

Classification and Function of Joints

Joints, or articulations, connect bones and allow for movement. They are classified by structure and function.

• Structural Classification:

  • Fibrous joints: Immovable (e.g., sutures in skull)

  • Cartilaginous joints: Slightly movable (e.g., intervertebral discs)

  • Synovial joints: Freely movable (e.g., shoulder, knee)

• Functional Classification:

  • Synarthroses: Immovable

  • Amphiarthroses: Slightly movable

  • Diarthroses: Freely movable

• Synovial Joint Structure:

  • Articular cartilage, joint cavity, synovial fluid, ligaments

• Types of Synovial Joints:

  • Ball-and-socket, hinge, pivot, saddle, plane, condyloid

Chapter 9: Muscles and Muscle Tissue

Types and Functions of Muscle Tissue

Muscle tissue is specialized for contraction and movement. There are three main types, each with unique characteristics and functions.

• Skeletal Muscle: Voluntary, striated, attached to bones

• Cardiac Muscle: Involuntary, striated, found in heart

• Smooth Muscle: Involuntary, non-striated, found in walls of organs

• Functions of Muscle Tissue:

  • Movement

  • Posture maintenance

  • Heat production

  • Stabilization of joints

Muscle Contraction

Muscle contraction is a complex process involving electrical and chemical signals.

• Sliding Filament Theory: Actin and myosin filaments slide past each other to shorten muscle.

• Neuromuscular Junction: Site where motor neuron stimulates muscle fiber.

• Excitation-Contraction Coupling: Sequence of events from nerve impulse to muscle contraction.

Chapter 10: The Muscular System

Major Muscles and Their Actions

The muscular system includes all skeletal muscles responsible for movement and posture. Understanding muscle names, locations, and actions is essential for anatomy students.

• Muscle Groups:

  • Head and neck: Facial expression, mastication

  • Trunk: Abdominal, back muscles

  • Upper limb: Shoulder, arm, forearm, hand muscles

  • Lower limb: Hip, thigh, leg, foot muscles

• Muscle Actions:

  • Flexion, extension, abduction, adduction, rotation

• Muscle Attachments:

  • Origin: Fixed attachment

  • Insertion: Movable attachment

Muscle Innervation

Muscles are controlled by nerves, which stimulate contraction and coordinate movement.

• Motor Units: One motor neuron and all muscle fibers it innervates

• Peripheral Nerves: Supply specific muscle groups

Chapter 11: Fundamentals of the Nervous System and Nervous Tissue

Overview of Nervous Tissue

The nervous system controls and coordinates body functions through electrical and chemical signals.

• Types of Nervous Tissue:

  • Neurons: Conduct impulses

  • Neuroglia: Support and protect neurons

• Structure of a Neuron:

  • Cell body, dendrites, axon

• Functions:

  • Sensory input

  • Integration

  • Motor output

Additional Info

• Exam covers chapters 6-11, focusing on bones, joints, muscles, and nervous tissue.

• Study guide includes key terms, functions, and examples for each chapter.