Histology, Bone Markings, and Skeletal System

Simple squamous epithelium

Single layer of flat cells; diffuses and filters; found in alveoli and blood vessels.

Simple cuboidal epithelium

Single layer of cube-shaped cells; secretes and absorbs; found in kidney tubules and thyroid.

Simple columnar epithelium

Single layer of rectangular cells; secretes and absorbs; found in stomach and intestines.

Pseudostratified columnar epithelium

Single layer of different-sized columnar cells; secretes mucus; found in trachea.

Stratified squamous epithelium

Multiple layers of flat cells; protects from abrasion; found in epidermis and mouth.

Stratified cuboidal epithelium

Multiple layers of cube-shaped cells; protection and secretion; found in sweat gland ducts.

Stratified columnar epithelium

Multiple layers of rectangular cells; protection and secretion; found in male urethra.

Transitional epithelium

Multiple layers of cells with umbrella cells; maintains barrier when stretched; urinary bladder.

Areolar connective tissue

Loose tissue with fibroblasts/mast cells; binds and cushions; found under epithelium.

Adipose tissue

Loose tissue with adipocytes; energy storage and insulation; found in hypodermis and abdomen.

Reticular connective tissue

Specialized loose tissue with reticular cells; structural framework; lymph nodes and spleen.

Dense regular connective tissue

Contains fibroblasts; strong attachment resisting tension in one direction; tendons and ligaments.

Dense irregular connective tissue

Contains fibroblasts; strength in many directions; found in dermis and organ capsules.

Elastic connective tissue

Contains fibroblasts; stretch and recoil; found in large arteries.

Hyaline cartilage

Contains chondrocytes; support and reduce friction; found in trachea and nose.

Elastic cartilage

Contains chondrocytes; flexible support; found in the external ear.

Fibrocartilage

Contains chondrocytes and fibroblasts; shock absorption; found in intervertebral discs.

Bone tissue

Contains osteocytes, osteoblasts, osteoclasts; support and mineral storage; skeleton.

Blood tissue

Contains erythrocytes, leukocytes, platelets; transport and clotting; blood vessels.

Skeletal muscle

Contains skeletal muscle fibers; voluntary movement and posture; attached to bones.

Cardiac muscle

Contains cardiomyocytes; pumps blood; found at the heart.

Smooth muscle

Contains smooth muscle cells; involuntary movement; walls of intestines and blood vessels.

Nervous tissue

Contains neurons and glial cells; sensation and rapid movement; brain and spinal cord.

Head (Epiphysis)

Rounded portion found at either end of the bone.

Neck (Metaphysis)

Widest part of the long bone.

Body (Diaphysis)

Central shaft running between proximal and distal ends of the bone.

Articular surface

Area of bone in proximity with neighboring bones.

Condyle

Rounded knobs that form articulations and absorb joint force.

Epicondyle

Bony area on or above a condyle for muscle/ligament attachment.

Protuberance

Swelling or bulging part of the bone.

Tubercle vs Tuberosity

Tubercle is a small rounded prominence; tuberosity is larger and rough.

Trochanter

Very large, irregular process of the femur for muscle attachment.

Spine (bone marking)

Sharp, slender projection useful for muscle or ligament attachment.

Linea (Line)

Long and narrow impression on a bone.

Facet

Flat, smooth area serving as an articular surface.

Crests and ridges

Prominent, raised edges connecting muscle and bone.

Foramen and fissure

Foramen: hole for vessels/nerves; Fissure: open slit or groove.

Meatus

Short, tube-like channel providing passage for nerves and vessels.

Fossa and fovea

Fossa: broad, shallow depression; Fovea: much smaller pit or depression.

Incisure and sulcus

Incisure: notch/indentation; Sulcus: furrow, groove, or fissure.

Sinus

A cavity or hollow space in a bone.

Frontal bone

Forms the forehead part of the skull.

Parietal bone

Forms the side and roof of the skull.

Temporal bone

Forms the sides and base of the skull.

Occipital bone

Forms the back and lower part of the skull.

Sphenoid bone

Smaller bone in the middle side of the skull.

Zygomatic bone

The cheek bones.

Maxilla bone

The upper jaw and upper lip bone.

Mandible bone

The lower jaw and chin bone.

Cervical vertebrae

7 vertebrae located right below the skull.

Thoracic vertebrae

12 vertebrae in the middle spine, each connecting to a rib.

Lumbar vertebrae

5 vertebrae in the lower spine supporting body weight.

Sacrum

Large, triangular bone at the base of the spine connecting to the pelvis.

Clavicles

Collar bones connecting the scapula and sternum.

Sternum

Long flat breastbone in the center of the chest.

Scapula

Shoulder blades connecting humerus and clavicle.

Ribs

Long curved bones forming the rib cage to protect thorax organs.

Humerus

Long arm bone running from shoulder to elbow.

Radius and ulna

Two bones running from the elbow to the wrist.

Pelvis bones

Consists of three major parts: Ilium, Ischium, and Pubis.

Femur

Largest thigh bone connecting pelvis to the knee.

Tibia

Larger shinbone connecting knee to ankle.

Fibula

Smaller calf bone in the lower leg connecting knee to ankle.