Human Anatomy: Body Regions and Movements

Body Regions

• Five principal body parts: head, neck, trunk (thorax & abdomen), upper limb, lower limb

Movement Terms

• Flexion/Extension
• Abduction/Adduction
• Rotation/Circumduction
• Pronation/Supination
• Inversion/Eversion

Directional Terms

• Anterior/Posterior (ventral/dorsal)
• Superior/Inferior
• Medial/Lateral
• Proximal/Distal
  • Proximal: Closer to the main body mass
  • Distal: Further from the main body mass
• Superficial/Deep
  • Superficial: Closer to the surface
  • Deep: Further from the surface
• Visceral/Parietal
• Ipsilateral/Contralateral
• Supine/Prone

Epithelial Tissue Types

• Simple Squamous: One layer of flat cells; lining of blood vessels, alveoli; diffusion, filtration, protection
• Stratified Squamous: Multiple layers, flattened outer cells; skin (keratinized), mouth/esophagus (non-keratinized); protection from drying and abrasion
• Simple Cuboidal: One layer of cube-shaped cells; kidney tubules, glands, ovary surfaces; secretion, absorption
• Stratified Cuboidal: Multiple layers of cube-shaped cells; sweat gland ducts, salivary gland ducts; secretion, absorption, protection
• Simple Columnar: One layer of elongated cells; digestive organs, uterine tubes; secretion, absorption
• Stratified Columnar: Multiple layers of elongated cells; male urethra, pharynx; protection, secretion
• Pseudostratified Columnar: Appears layered, but single layer; respiratory tract; secretion, moving mucus with cilia
• Transitional: Layers change shape depending on tension; urinary bladder, ureters; allows stretching

Goblet Cells

• Specialized cells in columnar epithelium
• Secrete mucus to lubricate surfaces
• Found in respiratory and digestive tracts

Connective Tissue (Tendon vs. Ligament)

• Tendon: Connects muscle to bone; dense regular connective tissue; strong, tensile strength
• Ligament: Connects bone to bone; dense regular connective tissue with more elastic fibers; flexibility and stability

Muscular Tissue Types

• Skeletal Muscle: Long, cylindrical, striated fibers, multiple nuclei; attached to skeleton; voluntary; body movement
• Smooth Muscle: Spindle-shaped, non-striated, single nucleus; walls of hollow organs (intestines, bladder); involuntary; moves substances through organs
• Cardiac Muscle: Branched, striated fibers, single nucleus, intercalated discs; heart; involuntary; pumps blood

Extracellular Junctions

• Gap Junctions: Plasma membrane channels; allow substance exchange; communication between cells; cardiac and smooth muscle
• Adhesion Junctions: Adjacent plasma membranes held by filaments; flexibility; skin cells

Skin Function

• Protection (trauma, UV radiation, pathogens)
• Regulation (water loss, body temperature)
• Sensory input (touch, pressure, temperature, pain)
• Excretion (removing waste through sweat)
• Vitamin D synthesis (produces vitamin D under UV light exposure)

Epidermis Layers

• Stratum Basale: Single row of actively dividing cells; keratinocytes, melanocytes, Langerhans cells, Merkel cells
• Stratum Spinosum: Spiny appearance due to keratin fibers
• Stratum Granulosum: Flattened cells with keratohyalin granules
• Stratum Lucidum (only in thick skin): Transparent layer
• Stratum Corneum: Tough, outermost layer of dead keratinized cells; prevents water loss, blocks pathogens

Degrees of Burns

• First Degree: Epidermis only; redness, pain (no blistering)
• Second Degree: Epidermis and part of dermis; blistering, severe pain
• Third Degree: Full-thickness burn; destroys entire skin layer; leathery appearance
• Fourth Degree: Extends into deeper tissues (like muscles or bones)

Skin Color in High-Altitude Regions

• High-altitude exposure = thinner atmosphere = more UV rays
• Increased melanin protects against UV damage, reduces skin cancer risk

Albinism

• Genetic disorder; defective melanin production
• Pale skin, light hair, increased sensitivity to sunlight, high susceptibility to burns and skin cancer

Athlete's Foot

• Fungal infection
• Affects toes and soles
• Symptoms: itching, scaling, redness

Skin Cancer (Melanoma)

• Malignant cancer arising from melanocytes
• Unusual moles or dark, irregular spots
• High risk in fair-skinned individuals with severe sunburn history
• Can metastasize rapidly
• Requires early detection for effective treatment

Bone Cells

• Osteoblasts: Produce bone matrix; facilitate bone growth; found on bone surface
• Osteocytes: Maintain bone tissue; derived from osteoblasts; embedded in bone matrix
• Osteoclasts: Break down bone tissue; for remodeling and calcium release; found on bone surface

Appendicular Skeleton Examples

• Upper Limbs: Humerus, radius, ulna, carpals, metacarpals, phalanges
• Lower Limbs: Femur, tibia, fibula, tarsals, metatarsals, phalanges
• Girdles: Pectoral (clavicle, scapula), Pelvic (ilium, ischium, pubis)

Vertebrae Regions

• Cervical: 7 vertebrae (C1-C7); supports head, neck movement
• Thoracic: 12 vertebrae (T1-T12); articulates with ribs
• Lumbar: 5 vertebrae (L1-L5); bears most weight, flexibility and movement
• Sacral: 5 fused vertebrae (S1-S5); forms sacrum, connects to pelvis
• Coccygeal: 3-5 fused vertebrae; tailbone

Gout

• Arthritis caused by uric acid crystals in joints
• Common sites: big toe, knees, ankles
• Symptoms: severe pain, redness, swelling, heat
• Cause: high uric acid levels (diet, genetics, kidney dysfunction)
• Management: anti-inflammatory meds, dietary changes (avoid purine-rich foods), hydration

Test your knowledge of human anatomy with this quiz focusing on body regions, movement terms, and epithelial tissue types. Learn about directional terms and how various body parts function and interact. This quiz is essential for anyone studying human biology or anatomy.