Lining Epithelium

Types of Epithelial Tissue

Flashcard 1

Term: What are the two main types of epithelial tissue?
Definition:

  1. Lining epithelia

  2. Glandular epithelia

Flashcard 2

Term: What are lining epithelia?
Definition: Epithelial tissues that cover or line internal organs, body cavities, and surfaces exposed to the external environment.

Flashcard 3

Term: Where are lining epithelia commonly found?
Definition:

  • Respiratory tract

  • Digestive tract

  • Airways

  • Skin

Flashcard 4

Term: What is the main function of lining epithelia?
Definition: They form a protective barrier for internal organs and body surfaces.

Flashcard 5

Term: What is glandular epithelium?
Definition: Epithelial tissue specialised to produce and secrete substances.

Flashcard 6

Term: How do glands form from glandular epithelium?
Definition: The epithelial cells grow down into the connective tissue to form a gland.

Classification of Lining Epithelia

Flashcard 7

Term: What two criteria are used to classify lining epithelial tissues?
Definition:

  1. Number of cell layers

  2. Shape of the cells at the free surface

Flashcard 8

Term: What determines whether an epithelium is simple or stratified?
Definition: The number of cell layers.

Flashcard 9

Term: What is simple epithelium?
Definition: Epithelium consisting of a single layer of cells.

Flashcard 10

Term: What is stratified epithelium?
Definition: Epithelium consisting of two or more layers of cells.

Flashcard 11

Term: How many layers can stratified epithelium contain?
Definition: Two layers to more than 100 layers of cells.

Flashcard 12

Term: Which cells determine the classification of stratified epithelia?
Definition: The shape of the cells on the top (free/apical) surface.

Cell Shapes in Epithelia

Flashcard 13

Term: What are squamous epithelial cells?
Definition: Flat cells that are wider than they are tall.

Flashcard 14

Term: What are cuboidal epithelial cells?
Definition: Cube-shaped cells that are as tall as they are wide.

Flashcard 15

Term: What are columnar epithelial cells?
Definition: Tall, narrow cells that are taller than they are wide.

Simple Epithelia

Flashcard 16

Term: What is simple squamous epithelium?
Definition: A single layer of flattened cells.

Flashcard 17

Term: What is the main function of simple squamous epithelium?
Definition: Rapid transport and diffusion of substances across the membrane.

Flashcard 18

Term: Where is simple squamous epithelium found?
Definition:

  • Blood vessels

  • Alveoli of the lungs

Flashcard 19

Term: Why is simple squamous epithelium suited for gas exchange?
Definition: Because it is extremely thin, allowing rapid diffusion of gases like oxygen.

Flashcard 20

Term: What is simple cuboidal epithelium?
Definition: A single layer of cube-shaped cells.

Flashcard 21

Term: What is the main function of simple cuboidal epithelium?
Definition: Secretion and formation of glands.

Flashcard 22

Term: Where is simple cuboidal epithelium commonly found?
Definition: Kidney tubules and ducts.

Flashcard 23

Term: What is simple columnar epithelium?
Definition: A single layer of tall column-shaped cells.

Flashcard 24

Term: Why are simple columnar cells well suited for absorption?
Definition: They contain many organelles that support absorption processes.

Flashcard 25

Term: Where is simple columnar epithelium found?
Definition: Gastrointestinal tract, especially the small intestine.

Flashcard 26

Term: What is pseudostratified columnar epithelium?
Definition: A single layer of cells that appears stratified but all cells contact the basement membrane.

Flashcard 27

Term: Why does pseudostratified epithelium appear stratified?
Definition: Because cell nuclei lie at different levels, creating the illusion of multiple layers.

Stratified Epithelia

Flashcard 28

Term: What is stratified squamous epithelium?
Definition: Multiple layers of flattened cells that provide protection.

Flashcard 29

Term: Where is stratified squamous epithelium found?
Definition:

  • Skin

  • Mouth

  • Esophagus

Flashcard 30

Term: What is stratified cuboidal epithelium?
Definition: Epithelium with multiple layers of cube-shaped cells.

Flashcard 31

Term: Where is stratified cuboidal epithelium found?
Definition:

  • Sweat glands

  • Salivary glands

  • Mammary glands

Flashcard 32

Term: What is stratified columnar epithelium?
Definition: Epithelium consisting of multiple layers with column-shaped surface cells.

Flashcard 33

Term: Where is stratified columnar epithelium found?
Definition: Parts of the male reproductive system, including the male urethra.

Specialised Lining Epithelia

Flashcard 34

Term: What are the four specialised epithelial tissues?
Definition:

  1. Endothelium

  2. Mesothelium

  3. Respiratory epithelium

  4. Transitional epithelium

Flashcard 35

Term: What is endothelium?
Definition: A specialised simple squamous epithelium lining blood vessels.

Flashcard 36

Term: What is the function of endothelium?
Definition: Allows rapid diffusion and exchange of molecules across blood vessel walls.

Flashcard 37

Term: Where is endothelium found?
Definition:

  • Cardiovascular system

  • Lymphatic system

Flashcard 38

Term: What is mesothelium?
Definition: A simple squamous epithelium with lubricating properties.

Flashcard 39

Term: What is the function of mesothelium?
Definition: Reduces friction between moving organs.

Flashcard 40

Term: Where is mesothelium found?
Definition: Around organs such as the lungs.

Keratinised vs Non-Keratinised Epithelium

Flashcard 41

Term: What is keratinised stratified squamous epithelium?
Definition: Epithelium containing dead cells filled with keratin in the outer layers.

Flashcard 42

Term: Where is keratinised stratified squamous epithelium found?
Definition: Skin.

Flashcard 43

Term: What is the function of keratin in epithelial tissue?
Definition: Creates a waterproof protective barrier.

Flashcard 44

Term: What is non-keratinised stratified squamous epithelium?
Definition: Stratified epithelium whose surface cells are alive and contain nuclei.

Flashcard 45

Term: Where is non-keratinised stratified squamous epithelium found?
Definition:

  • Mouth

  • Esophagus

  • Nostrils

  • Vagina

Respiratory Epithelium

Flashcard 46

Term: What is the full name of respiratory epithelium?
Definition: Pseudostratified ciliated columnar epithelium with goblet cells.

Flashcard 47

Term: What are goblet cells?
Definition: Cells that produce and secrete mucus.

Flashcard 48

Term: What is the mucociliary escalator?
Definition: A transport system that removes trapped particles from the respiratory tract.

Flashcard 49

Term: How does the mucociliary escalator work?
Definition:

  1. Goblet cells produce mucus that traps particles

  2. Cilia beat to move mucus upward toward the throat

Transitional Epithelium

Flashcard 50

Term: What is transitional epithelium?
Definition: Epithelium that can change shape depending on stretching.

Flashcard 51

Term: Where is transitional epithelium found?
Definition:

  • Bladder

  • Ureters

Flashcard 52

Term: Why is transitional epithelium important in the bladder?
Definition: It allows the bladder to expand when filling and contract when emptying.