Structural Organisation in Animals: Cells, Tissues, and Epithelial Types

Vocabulary practice flashcards covering cellular levels of organisation, fundamental animal tissue types, and the classifications, functions, and anatomical locations of simple epithelial tissues.

Cell

The structural and functional unit of a living organism.

Prokaryotic Cell

A cell that does not have a well-developed nucleus; for example, a bacterial cell.

Eukaryotic Cell

A cell that possesses a well-developed nucleus; examples include all animal and plant cells.

Unicellular Organism

An organism consisting of only one cell that performs all bodily functions, such as bacterial cells.

Multicellular Organism

An organism made of multiple cells where different groups of cells are responsible for different functions; examples include all animals.

Cellular Level of Organisation

The level of organization where a single cell independently performs specific vital functions like digestion, respiration, and reproduction.

Tissue Level of Organisation

The level of organization where similar cells combine to perform a specific function.

Organ Level of Organisation

The level of organization where different tissues combine to perform specific functions like digestion or excretion; examples include the stomach and kidney.

Organ System Level of Organisation

The level of organization where different organs combine to form a functional organ system, such as the kidneys, ureters, urinary bladder, and urethra forming the excretory system.

Tissue

A group of similar cells that combine together to perform a specific function with intercellular substances between them.

Epithelial Tissue

A tissue type present in the outer covering of the body and inner lining of ducts, tubules, glands, or organs, functioning in diffusion, absorption, filtration, and secretion.

Connective Tissue

A primary animal tissue type whose main function is linking and support.

Muscular Tissue

A primary animal tissue type responsible for locomotion and movement.

Nervous Tissue

A primary animal tissue type responsible for control and co-ordination.

Basement Membrane

An acellular and non-cellular proteinaceous layer on which epithelial tissue rests, separating it from the underlying connective tissue.

Avascularity in Epithelial Tissue

The characteristic of lacking blood vessels, requiring nutrients to pass from connective tissue to epithelial tissue via diffusion.

Simple Epithelial Tissue

An epithelial tissue made up of a single layer of cells that functions in diffusion, filtration, secretion, and absorption.

Compound Epithelium Tissue

An epithelial tissue composed of multiple layers of cells whose main function is providing protection against mechanical and chemical stress.

Simple Squamous Epithelium

A single layer of flattened, tile-like cells with irregular boundaries (margins) specialized for diffusion and filtration.

Pavement Membrane (Tesselated Membrane)

Alternative names for simple squamous epithelium, derived from its tile-like flattened cell appearance.

Locations of Simple Squamous Epithelium

Alveoli of lungs, Bowman's capsule of nephrons, and the endothelium of blood or lymph capillaries.

Simple Cuboidal Epithelium

An epithelial layer composed of cube-like shaped cells whose primary functions are absorption and secretion.

Normal Cuboidal Epithelium

Cuboidal epithelial cells featuring a centrally placed round nucleus, located in small ducts of secretory glands, germinal epithelium of gonads, distal convoluted tubule (DCT), collecting duct, and the ascending limb of loop of Henle.

Brush Bordered Cuboidal Epithelium

Cuboidal epithelial cells equipped with microvilli to increase surface area for absorption; located in the proximal convoluted tubule (PCT).

Simple Columnar Epithelium

An epithelial tissue composed of tall and slender column-shaped cells with oval-shaped nuclei located at the base of the cell.

Normal Columnar Epithelium

A sub-type of simple columnar epithelium present in the glands of the gut.

Brush Bordered Columnar Epithelium

Columnar epithelial cells bearing microvilli to increase surface area, present in the gastrointestinal tract (small intestine).

Kinociliated Columnar Epithelium

Columnar epithelial cells bearing cilia on their free surface, located in the fallopian tube and the bronchi and bronchioles of the respiratory tract.

Stereociliated Columnar Epithelium

Columnar epithelial cells possessing non-motile stereocilia, located in the vas deferens and epididymis.