Anatomy & Physiology: Cells, Tissues, Membranes & Glands

A complete set of vocabulary flashcards based on the provided Anatomy & Physiology study guide topic on cells, tissues, membranes, and glands.

The Cell

The basic structural and functional unit of all living organisms, averaging around $0.01\,mm$ ($10\,\mu m$) in size.

Cell Membrane

Double layer of lipids (phospholipids) and proteins that forms the outer boundary interacting with the external environment and regulates exchange.

Nucleus

Centrally located control center enclosed by the nuclear envelope that directs gene expression, cellular growth, metabolism, and protein synthesis.

Cytoplasm

Gel-like matrix suspending organelles, whose fluid portion is Cytosol; facilitates movement of substances and waste.

Cytosol

The fluid portion of the cytoplasm that facilitates movement of substances and waste.

Passive Transport

Movement across the plasma membrane down a concentration gradient without cellular energy/ATP.

Active Transport

Movement across the plasma membrane against concentration gradients that strictly requires ATP energy.

Ribosomes

Sites of protein synthesis found free in the cytoplasm or bound to the endoplasmic reticulum.

Rough ER

Membranous tubules and flattened sacs with attached ribosomes that manage protein synthesis, folding, quality control, and dispatch to the Golgi.

Smooth ER

Membranous structure lacking ribosomes that synthesizes lipids/carbohydrates, detoxifies harmful chemicals, and stores calcium ions.

Golgi Apparatus

Flattened membrane sacs stacked together that modify, package, and distribute proteins/lipids for internal use or secretion.

Lysosomes

Membrane-bound vesicles pinched off the Golgi that contain digestive enzymes to degrade excess materials and cellular waste.

Peroxisomes

Membrane-bound organelles for lipid and amino acid degradation that break down toxic hydrogen peroxide ($H_2O_2$).

Mitochondria

Major sites of ATP synthesis via cellular respiration when oxygen is available, known as the powerhouse of the cell.

Secretory Vesicles

Structures that store and transport substances between cells.

Centrosome

Microtubule-Organizing Center (MTOC) that regulates the cell cycle via spindle microtubule assembly.

Chromatin

Complex of DNA, RNA, and proteins forming chromosomes, responsible for DNA packaging and cell division.

Vacuoles

Organelles that store nutrients (water, NaCl, proteins/CHON, carbs/CHO) for survival and isolate waste products.

Microtubules

Tubulin polymers that support structure, form the spindle apparatus, and move chromosomes during cell division.

Microfilaments

Cytoskeletal structures that maintain and define cell shape and facilitate cell surface movements.

Intermediate Filaments

Cytoskeletal structures that provide tensile mechanical strength and structural support to cells and tissues.

Actin Filaments (Thin Filaments)

Contractile protein fibers responsible for cell movement and muscle contraction in striated muscle cells.

Tissues

Groups of specialized cells and their surrounding non-cellular extracellular matrix cooperating to carry out specialized functional activities.

Simple Epithelium

Epithelial classification consisting of 1 layer of cells, specialized for absorption, secretion, and filtration.

Stratified Epithelium

Epithelial classification consisting of 2 or more layers with the deepest layer on the basement membrane, specialized for protection against abrasion.

Pseudostratified Epithelium

Single cell layer of epithelium that falsely appears multi-layered.

Transitional Epithelium

Stratified epithelial cells that change shape from cuboidal/columnar to flat/squamous when distended.

Squamous Cells

Flat / scale-like epithelial cells.

Cuboidal Cells

Cube-shaped epithelial cells with equal width and height.

Columnar Cells

Tall and thin rectangular epithelial cells.

Connective Tissue

Diverse group of tissues providing structural support, physical connection, and framework, consisting of cells widely separated by an abundant extracellular matrix.

Nervous Tissue

Tissue that conducts electrical impulses called Action Potentials.

Cell Body (Soma)

Neuronal structure containing the nucleus; site of metabolic operations.

Dendrites

Neuronal structures that receive incoming action potentials/signals.

Axon

Neuronal structure that conducts action potentials away from the soma.

Skeletal Muscle

Striated (banded), voluntary muscle tissue attached to the skeleton with multinucleated cells that generate voluntary body movement.

Cardiac Muscle

Striated, involuntary muscle tissue with 1 nucleus per cell that forms the myocardium (heart wall) and pumps and propels blood.

Smooth Muscle

Non-striated, involuntary muscle tissue with 1 nucleus per cell located in walls of hollow visceral organs.

Mucous Membrane

Tissue membrane lining body cavities and canals opening directly to the exterior that protects, absorbs, and secretes mucus.

Serous Membrane

Tissue membrane lining closed internal cavities that secretes lubricating serous fluid to reduce friction.

Synovial Membrane

Connective tissue lining freely movable joint cavities that secretes synovial fluid rich in hyaluronic acid for smooth joint movement.

Cutaneous Membrane

The skin (stratified keratinized epithelium + dermis) covering the body exterior.

Endocrine Glands

Ductless glands that secrete hormones directly into interstitial fluid and the bloodstream.

Exocrine Glands

Glands that secrete chemical products onto epithelial surfaces via ducts.

Inflammation

Defensive vascular and cellular response to tissue injury or infection, categorized into Acute and Chronic.