Anatomy and Physiology: Directional Terminology, Microscope, Tissues, Integumentary and Skeletal Systems

Vocabulary review flashcards covering body directional terminology, compound microscope components, epithelial and connective tissues, integumentary system layers, and introductory skeletal structures.

Standard Anatomical Position

The standard reference position where the human body is erect, feet are only slightly apart, head and toes are pointed forward, arms hang at the sides, and palms face forward with thumbs pointing laterally.

Regional Anatomy

The study and description of specific areas of the body to help locate and understand anatomical structures.

Superior / Inferior

Directional terms meaning above (superior) and below (inferior) relative to another structure.

Anterior / Posterior

Directional terms meaning toward the front (anterior) and toward the back (posterior) of the body.

Cranial / Caudal

Directional terms meaning toward the head (cranial) and toward the tail or inferior end (caudal).

Ventral / Dorsal

Directional terms meaning toward the stomach or front (ventral) and toward the back (dorsal).

Medial / Lateral

Directional terms describing position in relation to the body midline; medial means towards the center, while lateral means towards the side.

Proximal / Distal

Directional terms applied to limbs or structures; proximal means closer to the point of attachment or origin, while distal means farther away.

Superficial / Deep

Directional terms describing depth; superficial means closer to the body surface or skin, while deep means farther away from the surface and closer to internal organs.

Plane

An imaginary flat surface that passes through the body, dividing it into two distinct parts.

Section

A physical slice or cut of the body or an organ made along a specific plane.

Median (Midsagittal) Plane

A longitudinal plane that runs directly down the middle of the body, dividing it into equal left and right halves.

Parasagittal Plane

A longitudinal plane parallel to the midline that divides the body into unequal left and right parts.

Coronal (Frontal) Plane

A longitudinal plane that divides the body into anterior (front) and posterior (back) portions.

Transverse Plane

A horizontal plane dividing the body into superior (upper) and inferior (lower) portions, producing cross sections.

Dorsal Body Cavity

A fluid-filled posterior body cavity that contains the cranial cavity (housing the brain) and the vertebral cavity (housing the spinal cord).

Ventral Body Cavity

A fluid-filled anterior body cavity containing the thoracic cavity (heart and lungs) and the abdominopelvic cavity (digestive organs, bladder, reproductive organs, and rectum).

Right Upper Quadrant (RUQ)

An abdominal quadrant containing the liver, stomach, gallbladder, and portions of the small and large intestines.

Left Upper Quadrant (LUQ)

An abdominal quadrant containing the liver, stomach, pancreas, left kidney, spleen, and portions of the small and large intestines.

Right Lower Quadrant (RLQ)

An abdominal quadrant containing the appendix, reproductive organs, and portions of the small and large intestines.

Left Lower Quadrant (LLQ)

An abdominal quadrant containing reproductive organs and portions of the small and large intestines.

Total Magnification Formula

The total magnifying power calculated as $\text{Total Magnification} = (\text{Power of ocular lens}) \times (\text{Power of objective lens})$, where the ocular lens is typically $10\times$.

Scanning Objective Lens

The $4\times$ objective lens on a compound microscope, which is used first along with the coarse adjustment knob to locate and focus on a specimen.

Tissue

A group of specialized cells that are similar in structure and perform a common function.

Histology

The microscopic study of tissues.

Apical Surface

The free, unattached upper surface of an epithelial tissue layer that borders an open space or cavity.

Basal Surface

The attached lower surface of an epithelial tissue layer that connects to the underlying basement membrane.

Avascular

Lacking blood vessels; a key property of epithelial tissues, which must rely on diffusion of nutrients from adjacent connective tissue.

Simple Squamous Epithelium

A single layer of flattened cells designed for diffusion and filtration; located in kidney glomeruli, lung alveoli, blood vessels, and lining of body cavities.

Simple Cuboidal Epithelium

A single layer of cube-like cells functioning in secretion and absorption; located in kidney tubules, gland ducts, and ovary surfaces.

Simple Columnar Epithelium

A single layer of tall cells functioning in absorption and mucus secretion; located throughout the digestive tract and gallbladder.

Stratified Squamous Epithelium

A thick tissue with multiple cell layers and flattened surface cells designed to protect underlying tissues from abrasion; forms the epidermis and linings of the esophagus, mouth, and vagina.

Extracellular Matrix

Non-cellular, non-living material surrounding connective tissue cells, consisting of ground substance and protein fibers (collagen, elastic, and reticular).

Mesenchyme

Embryonic tissue from which all adult connective tissues originate.

Loose Connective Tissue: Adipose

A loose connective tissue with a sparse matrix and closely packed adipocytes containing large fat droplets; insulates against heat loss, cushions organs, and stores energy.

Loose Connective Tissue: Areolar

A loose connective tissue featuring a gel-like matrix with collagen and elastic fibers, fibroblasts, and macrophages; cushions organs and surrounds capillaries under epithelia.

Dense Regular Connective Tissue

Dense connective tissue consisting primarily of parallel collagen fibers and fibroblasts; resists tensile stress in one direction and forms tendons, most ligaments, and aponeuroses.

Dense Irregular Connective Tissue

Dense connective tissue featuring irregularly arranged collagen fibers and fibroblasts; withstands tension from many directions and is located in the dermis and fibrous capsules of organs and joints.

Epidermis

The outer layer of skin composed of closely packed stratified squamous epithelial cells.

Dermis

The inner layer of skin composed of dense irregular connective tissue, divided into a papillary layer and a reticular layer.

Hypodermis

The deepest subcutaneous layer below the dermis, composed of adipose and connective tissues; technically not part of the skin.

Tactile (Meissner's) Corpuscle

A sensory nerve ending located in the dermal papillae that detects light touch.

Lamellar (Pacinian) Corpuscle

A sensory nerve receptor situated deep within the skin that senses deep pressure.

Arrector Pili

A bundle of smooth muscle attached to a hair follicle that contracts to pull the hair upright in response to cold or fear.

Eccrine Sweat Glands

Glands responsible for thermoregulation that secrete sweat directly onto the surface of the skin.

Apocrine Sweat Glands

Sweat glands that empty into hair follicles in axillary and perianal regions, becoming active during adolescence.

Stratum Basale

The deepest epidermal layer consisting of a single row of actively mitotic stem cells that continuously generate new keratinocytes.

Stratum Lucidum

A clear epidermal layer present exclusively in thick skin (palms and soles), located between the stratum granulosum and stratum corneum.

Stratum Corneum

The most superficial layer of the epidermis, composed of 20 to 30 layers of dead, flattened, keratinized cells.

Compact Bone

Dense and solid outer layer of bone constructed of structural units called osteons.

Osteon

The functional structural unit of compact bone, consisting of concentric rings of bone matrix called lamellae surrounding a central canal.

Lacunae

Small cavities or spaces within the calcified matrix of bone that house osteocytes and osteoblasts.

Canaliculi

Tiny microscopic canals connecting lacunae to each other and to the central canal for cellular communication and nutrient passage.

Spongy Bone

Porous, highly vascularized inner bone tissue structured as a meshwork of trabeculae and containing red bone marrow.

Axial Skeleton

The core division of the skeletal system comprising the skull, vertebral column, and thoracic cage, which protects internal organs and the spinal cord.

Appendicular Skeleton

The division of the skeletal system consisting of the bones of the upper and lower limbs and the girdles that attach them to the axial skeleton.

Sesamoid Bones

A specialized category of short bones formed within tendons, such as the patella and pisiform.