Cell Transport, Tissues, and the Integumentary System

Vocabulary flashcards covering the key terms and definitions from Chapters 3 (Cell Transport), 6 (Tissues and Membranes), and 7 (Integumentary System).

Passive Transport

Movement of molecules from high to low concentration without ATP; includes diffusion, facilitated diffusion, osmosis, and filtration.

Active Transport

Energy-requiring movement of molecules from low to high concentration; uses ATP and includes pumps, endocytosis, and exocytosis.

Diffusion

Passive movement of a solute from an area of higher to lower concentration (e.g., oxygen into cells).

Facilitated Diffusion

Passive transport that uses membrane proteins to move large or charged molecules such as glucose or ions down their gradient.

Osmosis

Diffusion of water across a selectively permeable membrane from a region of high water concentration to low water concentration.

Filtration

Passive movement of substances from high to low pressure, as in blood vessels or the kidneys.

Isotonic Solution

A solution with the same solute concentration as the cell; no net water movement.

Hypotonic Solution

A solution with fewer solutes than the cell; water enters the cell, possibly causing swelling.

Hypertonic Solution

A solution with more solutes than the cell; water leaves the cell, causing shrinkage.

Transport Pump

Protein that uses ATP to move substances against their concentration gradient.

Na⁺/K⁺ Pump

Active transport mechanism that expels 3 Na⁺ out of and brings 2 K⁺ into the cell using ATP.

Endocytosis

ATP-dependent process of bringing large particles or fluid into the cell via vesicles.

Phagocytosis

“Cell eating”; type of endocytosis that engulfs solid particles.

Exocytosis

ATP-dependent process of vesicles fusing with the plasma membrane to release contents outside the cell.

Epithelial Tissue

Protective sheet lining internal and external surfaces; functions in protection, absorption, secretion, and diffusion.

Simple Squamous Epithelium

Single flat cell layer specialized for diffusion (e.g., alveoli of lungs).

Simple Cuboidal Epithelium

Single cube-shaped cell layer specialized for secretion (e.g., kidney tubules, glands).

Simple Columnar Epithelium

Single tall cell layer specialized for absorption (e.g., digestive tract).

Stratified Squamous Epithelium

Multiple layers of flat cells providing protection (e.g., skin, mouth).

Transitional Epithelium

Stretchable epithelium lining the bladder and urinary tract.

Connective Tissue

Most abundant tissue; binds and supports; characterized by cells in an extracellular matrix of collagen and elastin.

Matrix

Non-living extracellular material of connective tissue composed of protein fibers and ground substance.

Collagen

Strong protein fiber providing tensile strength in connective tissues.

Elastin

Elastic protein fiber providing stretch and recoil in connective tissues.

Loose Connective Tissue

Areolar tissue under skin; contains fibroblasts and loose fiber arrangement.

Adipose Tissue

Fat-storing connective tissue; cells are adipocytes; functions in energy storage and insulation.

Cartilage

Supportive connective tissue with chondrocytes in lacunae; flexible yet firm.

Osseous Tissue

Bone tissue containing osteoblasts, osteocytes, and osteoclasts within a rigid matrix.

Blood

Fluid connective tissue composed of red and white blood cells in plasma.

Lymph

Fluid connective tissue involved in immune response and fluid balance.

Nervous Tissue

Tissue of brain, spinal cord, and nerves specialized for communication.

Neuron

Excitable nerve cell that generates and transmits electrical signals.

Neuroglia

Supportive cells that protect, nourish, and insulate neurons.

Muscle Tissue

Tissue with cells that contract; includes skeletal, smooth, and cardiac types.

Skeletal Muscle

Voluntary muscle attached to bones; striated fibers.

Smooth Muscle

Involuntary, non-striated muscle in walls of organs and vessels.

Cardiac Muscle

Involuntary, striated muscle of the heart; cells connected by intercalated discs.

Tissue Repair

Replacement of damaged tissue; epithelial and connective tissues repair well, muscle and nervous form scar due to lack of mitosis.

Scar Tissue

Nonfunctional collagenous tissue replacing normal tissue after injury.

Membrane

Thin sheet of tissue that lines, covers, or surrounds structures.

Cutaneous Membrane

The skin; exterior epithelial membrane exposed to air.

Mucous Membrane

Epithelial membrane lining body passages open to exterior (digestive, respiratory, urinary, reproductive).

Serous Membrane

Epithelial membrane lining closed body cavities; secretes lubricating serous fluid.

Visceral Layer

Serous membrane layer that adheres directly to an organ surface.

Parietal Layer

Serous membrane layer that lines the body cavity wall.

Pericardium

Serous membrane surrounding the heart.

Pleura

Serous membrane surrounding the lungs.

Peritoneum

Serous membrane lining the abdominal cavity and organs.

Periosteum

Connective tissue membrane covering bone surfaces.

Meninges

Connective tissue membranes enveloping brain and spinal cord.

Integumentary System

System consisting of skin, hair, nails, and glands; functions in protection, secretion, sensation, and temperature regulation.

Epidermis

Superficial, avascular skin layer composed of keratinized stratified squamous epithelium.

Dermis

Middle skin layer of connective tissue containing blood vessels, nerves, and glands.

Hypodermis

Deep subcutaneous layer of adipose connective tissue anchoring skin to underlying structures.

Keratinocyte

Primary epidermal cell producing keratin for waterproofing.

Melanocyte

Pigment-producing epidermal cell responsible for skin color.

Stratum Basale

Deepest epidermal layer where mitosis occurs.

Stratum Corneum

Outermost epidermal layer composed of dead, keratinized cells.

Sebaceous Gland

Oil gland that secretes sebum into hair follicles for lubrication.

Sudoriferous Gland

Sweat gland aiding thermoregulation and waste removal.

Apocrine Gland

Sweat gland in axillary and genital areas; active at puberty.

Eccrine Gland

Widely distributed sweat gland important for temperature control.

Ceruminous Gland

Modified sweat gland in external ear canal that produces earwax (cerumen).

Mammary Gland

Modified sweat gland that produces milk.

Nail

Hard keratinized plate protecting digit tips; contains nail body, root, and lunula.

Lunula

Pale crescent at nail base representing active nail matrix.

Thermoregulation

Maintenance of body temperature via sweating and blood vessel diameter changes.

Vasodilation

Widening of skin blood vessels to release heat.

Vasoconstriction

Narrowing of skin blood vessels to conserve heat.

Shivering

Involuntary skeletal muscle contractions generating heat when body temperature drops.