Body Cavities and Regional Terms

Body Cavities

The human body contains several major cavities that house vital organs and structures. Understanding these cavities is essential for locating anatomical features and describing medical conditions.

• Cranial cavity: Contains the brain.

• Thoracic cavity: Contains the heart and lungs.

• Abdominal cavity: Contains digestive organs.

• Pelvic cavity: Contains reproductive and some excretory organs.

• Spinal cavity: Contains the spinal cord.

Regional Terms

Regional terms are used to describe specific areas of the body, aiding in precise communication in anatomy and medicine.

• Cephalic: Head

• Cervical: Neck

• Thoracic: Chest

• Abdominal: Abdomen

• Pelvic: Pelvis

• Brachial: Arm

• Antebrachial: Forearm

• Carpal: Wrist

• Femoral: Thigh

• Crural: Leg

• Tarsal: Ankle

• Orbital: Eye region

• Plantar: Sole of foot

Nine Regions of the Abdomen

Abdominal Regions

The abdomen is divided into nine regions for anatomical and clinical reference.

• Epigastric

• Umbilical

• Hypogastric

• Right/Left Hypochondrium

• Right/Left Lumbar

• Right/Left Iliac

Integumentary System

Skin Structure

The integumentary system protects the body and includes the skin and its derivatives.

• Epidermis: Outermost layer

• Dermis: Middle layer

• Subcutaneous (hypodermis): Deepest layer

• Sebaceous gland: Produces oil

• Sudoriferous gland: Produces sweat

• Arrector pili muscle: Causes hair to stand up

Hair Structure

• Shaft: Visible part of hair

• Bulb: Base of hair follicle

• Root: Part of hair below the skin

• Follicle: Structure from which hair grows

Cell Structure

Cell Organelles

Cells are the basic units of life, containing organelles that perform specific functions.

• Mitochondria: Powerhouse of the cell

• Nucleus: Contains genetic material

• Endoplasmic reticulum: Protein and lipid synthesis

• Golgi apparatus: Packaging and transport

Histology

Tissue Types

Histology is the study of tissues. The four basic tissue types are epithelial, connective, muscular, and nervous tissue.

• Epithelial tissue: Covers surfaces and lines cavities. Types include simple squamous, simple cuboidal, simple columnar, stratified squamous, transitional, pseudostratified ciliated columnar.

• Connective tissue: Supports and binds other tissues. Types include areolar, adipose, dense regular, dense irregular, hyaline cartilage, elastic cartilage, osseous (bone), blood.

• Muscular tissue: Responsible for movement. Types include skeletal, cardiac, and smooth muscle.

• Nervous tissue: Conducts electrical impulses. Main cell type is the neuron.

Skeletal System

Skull Anatomy

The skull is composed of several bones and features important for protection and function.

• Frontal bone: Contains supraorbital foramen, glabella

• Parietal bone: Sagittal suture, coronal suture, lambdoid suture

• Temporal bone: Squamous suture, external auditory meatus, styloid process, mastoid process, zygomatic process, mandibular fossa, jugular foramen

• Occipital bone: Lambdoid suture, foramen magnum, occipital condyle, external occipital protuberance (EOP)

• Sphenoid: Greater/lesser wings, sella turcica, optic canal, foramen ovale

• Ethmoid bone: Cribriform plates, olfactory foramina

• Mandible: Body, mandibular condyle, coronoid process, mental foramen, alveoli

• Maxilla: Alveoli, intermaxillary suture, zygomatic process

• Other bones: Zygomatic, palatine, lacrimal, nasal, vomer

Vertebral Column

The vertebral column supports the body and protects the spinal cord. It is divided into regions based on vertebrae type.

• Cervical vertebrae: 7 (including atlas and axis)

• Thoracic vertebrae: 12

• Lumbar vertebrae: 5

• Key features: Vertebral body, spinous process, transverse process, vertebral foramen, intervertebral foramen (IVF)

Thoracic Cage

• Hyoid bone: Supports tongue

• Ribs: 12 pairs (7 true, 5 false; 2 floating)

• Sternum: Body, manubrium, xiphoid process

• Coccyx: Tailbone

Upper Extremity Bones

• Clavicle

• Scapula: Acromion process, coracoid process, glenoid fossa, spine, supraspinous fossa, infraspinous fossa, subscapular fossa

• Humerus: Head, greater/lesser tubercles, capitulum, trochlea, deltoid tuberosity, olecranon fossa, coronoid fossa, olecranon process

• Radius: Head, neck, styloid process

• Ulna: Olecranon process, coronoid process, styloid process

Pelvic Bones

• Ilium: ASIS (anterior superior iliac spine), PSIS (posterior superior iliac spine), iliac crest, greater sciatic notch

• Ischium: Ischial spine, ischial tuberosity, lesser sciatic notch

• Pubis: Pubic symphysis

• Obturator foramen, acetabulum

Lower Extremity Bones

• Femur: Head, neck, greater/lesser trochanters, medial/lateral condyles, medial/lateral epicondyles

• Patella: Kneecap

• Tibia: Tibial tuberosity, lateral/medial condyles, medial malleolus

• Fibula: Lateral malleolus, head

• Tarsals: 7 bones (talus, calcaneus, etc.)

• Metatarsals

• Phalanges: Distal, middle, proximal

Key Comparative Table: Types of Epithelial Tissue

Additional info:

• Some anatomical terms and features were inferred for completeness and clarity.

• Table entries for epithelial tissue types were expanded for academic context.