A&P 2.1-2.3

Cell

"The basic unit of life."

Cell Theory

"A fundamental concept in biology stating that all living things are composed of cells

Totipotent

"A cell that has the potential to make any other cell in the body; e.g.

Pluripotent

"A stem cell that can make most

Multipotent

"A stem cell that can make a limited range of cells within a specific tissue type."

Plasma Membrane

"The outer boundary of a cell; it is selectively permeable and separates intracellular fluids from extracellular fluids."

Fluid Mosaic Model

"A model describing the plasma membrane as a flexible phospholipid bilayer with proteins and other molecules embedded in it

Phospholipid Bilayer

"A double layer of phospholipids that forms the core of the plasma membrane

Integral Protein

"A protein that spans the entire width of the plasma membrane; often involved in transport."

Peripheral Protein

"A protein that ""floats"" on one side of the plasma membrane; may act as an enzyme or anchor."

Glycoprotein

"A protein with a carbohydrate attached; often functions as a cell identity marker."

Glycolipid

"A lipid with a carbohydrate attached; found on the extracellular surface of the plasma membrane."

Nucleus

"A double-membraned organelle that houses DNA and controls cell activities."

Chromatin

"The complex of DNA and proteins found within the nucleus of a cell."

Chromosomes

"Tightly wound

Nucleolus

"A protein-rich area within the nucleus responsible for assembling ribosomes."

Mitochondria

"Organelles that perform cellular respiration to produce ATP (energy) for the cell."

Ribosomes

"Cellular structures that synthesize proteins."

Rough Endoplasmic Reticulum (Rough ER)

"An organelle studded with ribosomes; involved in protein synthesis and modification."

Smooth Endoplasmic Reticulum (Smooth ER)

"An organelle that synthesizes lipids and detoxifies substances."

Golgi Apparatus

"An organelle that sorts

Lysosomes

"Organelles that contain digestive enzymes to break down endocytosed materials and cellular waste."

Peroxisomes

"Organelles that break down and detoxify various substances

Cytoskeleton

"An internal network of protein filaments that provides structural support and enables cell movement and division."

Microtubules

"Tubular proteins that form part of the cytoskeleton; act as roads for intracellular transport and form cilia and flagella."

Cilia

"Short

Flagella

"Long

Microvilli

"Very small

Extracellular Matrix (ECM)

"A collection of proteins and polysaccharides secreted by cells that helps hold cells together and provides structural support."

Cell Junctions

"Specialized structures that bind most body cells together."

Tight Junctions

"Impermeable junctions that seal adjacent cells together

Gap Junctions

"Junctions with tubelike proteins that allow ions and small molecules to pass directly from one cell to another."

Desmosomes

"Junctions that act like rivets

Microscopy

"The use of a microscope to view small objects."

Compound Light Microscope

"A microscope that uses a light source and two sets of lenses (objective and ocular) to illuminate and magnify a specimen."

Ocular Lens (Eyepiece)

"The lens you look through

Objective Lenses

"The set of lenses on a revolving nosepiece (e.g.

Total Magnification

"Calculated by multiplying the magnification of the ocular lens by the magnification of the objective lens."

Stage

"The platform on a microscope that holds the slide."

Diaphragm

"The part of the microscope that controls the amount of light reaching the specimen."

Coarse Adjustment Knob

"The large knob used for initial

Fine Adjustment Knob

"The small knob used for fine-tuning the focus

Fixation

"The process of preserving a tissue specimen for microscopy

Sectioning

"The process of slicing a specimen into very thin sections for microscopy

Staining

"The process of applying dyes to a specimen to enhance contrast and make specific structures visible."

Histology

"The study of tissues."

Epithelial Tissue

"Tissue that lines and protects interior and exterior surfaces of the body and forms glands."

Polarity

"A characteristic of epithelial tissue having an apical (free) surface and a basal (attached) surface."

Apical Surface

"The upper

Basal Surface

"The lower

Basement Membrane

"A thin

Avascular

"Lacking blood vessels; a characteristic of epithelial tissue

Innervated

"Containing nerve endings; a characteristic of epithelial tissue."

Regeneration

"The ability to replace lost or damaged cells; epithelial tissue has a high regenerative capacity."

Simple Epithelium

"A single layer of epithelial cells; adapted for absorption

Stratified Epithelium

"Multiple layers of epithelial cells; primarily for protection."

Squamous

"Flattened and scale-like epithelial cell shape."

Cuboidal

"Boxy

Columnar

"Tall

Simple Squamous Epithelium

"A single layer of flattened cells; found in areas where rapid diffusion is needed

Simple Cuboidal Epithelium

"A single layer of boxy cells; found in ducts and secretory parts of small glands (e.g.

Simple Columnar Epithelium

"A single layer of tall cells; often specialized for absorption and secretion

Pseudostratified Columnar Epithelium

"A single layer of cells of varying heights

Stratified Squamous Epithelium

"Multiple layers of cells with apical cells being flattened; the most widespread epithelium

Stratified Cuboidal Epithelium

"Typically two layers of cube-shaped cells; rare

Stratified Columnar Epithelium

"Multiple layers of columnar cells; rare

Transitional Epithelium

"A stratified epithelium that can stretch and recoil; found in the urinary bladder."

Glandular Epithelium

"Epithelium that is specialized to produce and secrete substances."

Endocrine Glands

"Ductless glands that secrete hormones directly into the bloodstream."

Exocrine Glands

"Glands that secrete their products onto body surfaces or into body cavities through ducts."

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