Comprehensive Study Notes: Anatomy & Physiology – Integumentary, Skeletal, Articulations, and Muscular Systems

Chapter 5 – Integumentary System

Structure and Function of the Integument

The integumentary system consists of the skin and its accessory structures, providing protection, sensation, and regulation. Special emphasis is placed on the epidermis and dermis.

• Cutaneous Membrane: Composed of the epidermis (superficial layer) and dermis (deeper layer).

• Hypodermis: Subcutaneous tissue beneath the dermis, primarily adipose tissue.

• Functions: Protection, thermoregulation, sensation, excretion, and synthesis of vitamin D.

Layers of the Epidermis and Dermis

The skin is organized into distinct layers, each with specialized cells and functions.

• Epidermis Layers:

  • Stratum corneum

  • Stratum lucidum (only in thick skin)

  • Stratum granulosum

  • Stratum spinosum

  • Stratum basale

• Dermis Layers:

  • Papillary layer: Contains dermal papillae, capillaries, and sensory receptors.

  • Reticular layer: Dense irregular connective tissue, provides strength and elasticity.

Melanin and Skin Color

Melanin is a pigment produced by melanocytes in the stratum basale, responsible for skin color and protection against UV radiation.

• Distribution and amount of melanin determine skin tone.

• Additional info: Melanin also protects DNA from UV-induced damage.

Accessory Structures: Hair and Nails

Hair and nails are keratinized structures derived from the epidermis, serving protective and sensory functions.

• Hair: Consists of the root, follicle, and shaft. Functions include protection, sensation, and thermoregulation.

• Nails: Composed of the nail plate, bed, matrix, lunula, and cuticle (eponychium). Functions include protection and aiding in manipulation of objects.

Glands of the Skin

The skin contains several types of glands with distinct functions.

• Sudoriferous (Sweat) Glands: Eccrine (merocrine) glands for thermoregulation; apocrine glands in axillary and genital areas.

• Sebaceous Glands: Secrete sebum for lubrication and waterproofing.

• Ceruminous Glands: Produce earwax (cerumen) in the external ear canal.

Classification of Burns

Burns are classified by degree based on depth and tissue damage.

Degree	Description
First degree	Superficial, affects only the epidermis
Second degree	Partial thickness, affects epidermis and part of dermis
Third degree	Full thickness, destroys epidermis and dermis

Types of Skin Cancer

Skin cancer is classified by the cell type of origin.

Type	Description
Basal cell carcinoma	Originates from basal cells; most common, least dangerous
Squamous cell carcinoma	Originates from squamous cells; can metastasize
Malignant melanoma	Originates from melanocytes; most dangerous

Chapter 6 – Bones and Bone Tissue

Functions of the Skeletal System

The skeletal system provides structure, protection, movement, mineral storage, and blood cell production.

• Support: Framework for the body

• Protection: Shields vital organs

• Movement: Attachment for muscles

• Mineral Storage: Reservoir for calcium and phosphorus

• Hematopoiesis: Blood cell formation in bone marrow

Classification of Bones

Bones are classified by shape and structure.

Type	Examples
Long bones	Femur, humerus
Short bones	Carpals, tarsals
Flat bones	Skull, ribs
Irregular bones	Vertebrae, pelvis
Sesamoid bones	Patella

Bone Structure and Remodeling

Bones consist of compact and spongy tissue, and undergo continuous remodeling.

• Compact bone: Dense, provides strength

• Spongy bone: Contains trabeculae, supports marrow

• Remodeling: Osteoblasts build bone, osteoclasts resorb bone

Key processes:

• Bone deposition

• Bone resorption

• Fracture healing: Hematoma, soft callus, hard callus, remodeling

Chapter 7 – Skeletal System

Bone Markings and Features

Bones have distinct markings for muscle attachment, articulation, and passage of nerves and vessels.

• Examples: Tuberosity, groove, condyle, foramen, process, spine

Axial and Appendicular Skeleton

The skeleton is divided into axial (skull, vertebral column, thoracic cage) and appendicular (limbs, girdles) components.

• Axial: Skull, vertebrae, ribs, sternum

• Appendicular: Limbs, pelvic and pectoral girdles

Developmental and Comparative Anatomy

Comparison of fetal and adult skulls, and male vs. female pelvic bones, highlights anatomical differences related to function.

• Fetal skull: Fontanels allow for growth and birth

• Pelvic differences: Female pelvis is wider for childbirth

Chapter 8 – Articulations

Classification of Joints

Joints are classified structurally and functionally.

Structural Type	Examples
Fibrous	Sutures, gomphoses
Cartilaginous	Synchondroses, symphyses
Synovial	Hinge, ball-and-socket, saddle

• Functional Types: Synarthrosis (immovable), amphiarthrosis (slightly movable), diarthrosis (freely movable)

Movements at Joints

Joints permit various movements essential for locomotion and manipulation.

• Flexion/Extension

• Abduction/Adduction

• Rotation/Circumduction

• Special movements: Elevation, depression, protraction, retraction, inversion, eversion

Joint Pathologies

Common joint disorders include arthritis and dislocations.

• Rheumatoid arthritis: Autoimmune inflammation

• Osteoarthritis: Degenerative joint disease

Chapter 9 – Muscular System

Muscle Naming and Functions

Muscles are named based on location, shape, size, direction, number of origins, and action.

• Major functions: Movement, posture, heat production, joint stabilization

Muscle Attachments and Actions

Muscles attach to bones via tendons and produce movement by contracting.

• Origin: Fixed attachment

• Insertion: Movable attachment

• Agonist: Prime mover

• Antagonist: Opposes prime mover

• Synergist: Assists agonist

• Fixator: Stabilizes origin

Levers in the Muscular System

Muscles and bones form lever systems to facilitate movement.

• First-class lever: Fulcrum between effort and load

• Second-class lever: Load between fulcrum and effort

• Third-class lever: Effort between fulcrum and load

Chapter 10 – Muscle System Physiology

Microscopic Anatomy of Muscle Tissue

Muscle tissue is composed of fibers containing myofibrils, which are made up of sarcomeres.

• Skeletal muscle: Striated, voluntary

• Cardiac muscle: Striated, involuntary, intercalated discs

• Smooth muscle: Non-striated, involuntary

Sliding Filament Theory

Muscle contraction occurs via the sliding of actin and myosin filaments within the sarcomere.

• Key proteins: Actin, myosin, troponin, tropomyosin

• Process: Calcium ions bind to troponin, exposing binding sites for myosin on actin, leading to contraction

Equation:

$\text{Force} = \text{Mass} \times \text{Acceleration}$

Muscle Contraction and Relaxation

Contraction is initiated by action potentials and regulated by calcium ions; relaxation occurs when calcium is reabsorbed.

• Excitation-contraction coupling: Links electrical signal to contraction

• Fatigue: Decline in ability to generate force

Types of Muscle Contractions

Type	Description
Isotonic	Muscle changes length (concentric/eccentric)
Isometric	Muscle length remains constant

Cardiac and Smooth Muscle Features

Cardiac muscle contains intercalated discs for synchronized contraction; smooth muscle contracts via dense bodies and is regulated by calmodulin.

• Cardiac: Autorhythmic, striated

• Smooth: Non-striated, single-unit or multi-unit types

Additional info: These notes synthesize and expand upon the provided outline, offering definitions, examples, and academic context for key Anatomy & Physiology topics.