Chapter 5: Bones and Osseous Tissue

Cartilage Types and Locations

Cartilage is a flexible connective tissue found in various locations throughout the body, providing support and cushioning in joints.

• Hyaline cartilage: Found in the nose, trachea, and at the ends of long bones.

• Elastic cartilage: Located in the ear and epiglottis.

• Fibrocartilage: Present in intervertebral discs and pubic symphysis.

Parts and Functions of a Long Bone

Long bones are characterized by a shaft and two ends, and are crucial for movement and support.

• Diaphysis: The shaft, composed mainly of compact bone.

• Epiphyses: The ends of the bone, containing spongy bone and red marrow.

• Periosteum: A dense membrane covering the outer surface of bones.

• Epiphyseal plate: Growth plate found in children and adolescents.

Bone Cells and Functions

• Osteoblasts: Cells that build new bone tissue.

• Osteocytes: Mature bone cells maintaining bone matrix.

• Osteoclasts: Cells that break down bone tissue.

Hormonal Control of Bone

• Parathyroid hormone (PTH): Increases blood calcium by stimulating osteoclasts.

• Calcitonin: Lowers blood calcium by inhibiting osteoclast activity.

Bone Classification

• Long bones: Femur, humerus

• Short bones: Carpals, tarsals

• Flat bones: Skull, ribs

• Irregular bones: Vertebrae, pelvis

Chapter 6 & 7: The Skeleton

Axial Skeleton

The axial skeleton forms the central axis of the body and includes the skull, vertebral column, and thoracic cage.

• Skull bones: Frontal, parietal, occipital, ethmoid, facial bones, hyoid bone

• Vertebral column: Cervical, thoracic, lumbar, sacral, coccygeal regions

• Thoracic cage: Ribs and sternum

Appendicular Skeleton

The appendicular skeleton includes the limbs and girdles, facilitating movement.

• Pectoral girdle: Clavicle and scapula

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

• Pelvic girdle: Hip bones

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

Vertebral Curvatures

• Cervical and lumbar: Lordotic (concave posteriorly)

• Thoracic and sacral: Kyphotic (convex posteriorly)

Chapter 8: Joints

Functional Classification of Joints

Joints are classified by their movement capabilities.

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

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

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

Types of Synovial Joints

• Plane: Gliding movements (e.g., intercarpal joints)

• Hinge: Flexion and extension (e.g., elbow)

• Pivot: Rotation (e.g., proximal radioulnar joint)

• Flexion, extension, abduction, adduction (e.g., wrist)

• Saddle: Similar to condyloid but with greater range (e.g., thumb)

• Ball-and-socket: Multiaxial movement (e.g., shoulder, hip)

Range of Movement at Synovial Joints

• Angular movements: Flexion, extension, abduction, adduction

• Circular movements: Rotation, circumduction

• Special movements: Supination, pronation, inversion, eversion

Chapter 9: Myology I

Types of Muscle Tissue

Muscle tissue is classified into three types, each with distinct structure and function.

• Skeletal muscle: Voluntary, striated, attached to bones

• Cardiac muscle: Involuntary, striated, found in the heart

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

Skeletal Muscle Structure

• Connective tissue components: Endomysium, perimysium, epimysium

• Muscle fiber: The cell of skeletal muscle, containing myofibrils

• Sarcolemma: Muscle cell membrane

• Sarcoplasmic reticulum (SR): Stores calcium ions

• Sarcomere: Functional contractile unit of muscle

Myofilaments

• Thick filaments: Composed of myosin

• Thin filaments: Composed of actin, troponin, tropomyosin

Muscle Contraction

• Isotonic contraction: Muscle changes length (movement occurs)

• Isometric contraction: Muscle does not change length (no movement)

Chapter 9: Myology II

Muscle Actions

• Agonist: Prime mover of a muscle action

• Antagonist: Opposes the action of the agonist

• Synergist: Assists the agonist

• Fixator: Stabilizes the origin of the agonist

Lever Systems

Muscles and bones interact as lever systems to produce movement.

• First-class lever: Fulcrum between effort and load (e.g., neck)

• Second-class lever: Load between fulcrum and effort (e.g., standing on tiptoe)

• Third-class lever: Effort between fulcrum and load (e.g., biceps curl)

Naming Skeletal Muscles

• Location: e.g., frontalis (forehead)

• Shape: e.g., deltoid (triangle)

• Size: e.g., maximus (largest)

• Direction of fibers: e.g., rectus (straight)

• Number of origins: e.g., biceps (two origins)

• Attachment sites: e.g., sternocleidomastoid

• Action: e.g., flexor, extensor

Digestive System

Digestive Tract Layers

The digestive tract consists of several layers, each with specific functions.

• Mucosa: Innermost layer, contains epithelial cells and glands

• Submucosa: Connective tissue, blood vessels, nerves

• Muscularis externa: Smooth muscle for peristalsis

• Serosa: Outermost layer, protective covering

Parts of the Digestive Tract

• Stomach: Divided into regions (cardia, fundus, body, pylorus); contains gastric mucosa and sphincters

• Small intestine: Subdivided into duodenum, jejunum, ileum; contains villi and valves

• Large intestine: Includes cecum, colon, rectum, anal canal; contains divisions and sphincters

• Liver: Functions include secretion, metabolism, and detoxification; contains portal triad

• Gall bladder: Stores and concentrates bile

• Pancreas: Produces digestive enzymes and hormones; main pancreatic duct

Nerve Supply

• Intrinsic: Enteric nervous system within the digestive tract

• Extrinsic: Autonomic nervous system (sympathetic and parasympathetic)

Digestive Enzymes

Digestive enzymes are crucial for breaking down food into absorbable nutrients.

Key Equations

• Muscle contraction (sliding filament theory):

• Levers (mechanical advantage):

Additional info: Some content was expanded for clarity and completeness, including definitions, examples, and equations relevant to the listed topics.