Epithelial tissue

Question 1

Describe the first two characteristics of an epithelial cell

Answer 1

1- Covers and protects surfaces inside and outside the body. Form boundaries between the internal and external parts of the body
2- Distinct cell surfaces. Free surface, Lateral surface and Basal surface

Question 2

Describe the last two characteristics of an epithelial cell

Answer 2

3- Avascular (Does not have a direct blood supply. Receives blood from underlying tissue) and innervated (Has nerve cells).
4- Ability to regenerate. Can divide and produce new cells if cells are damaged

Question 3

What are the three types of cell layers

Answer 3

Simple: single layer
Stratified: More than one layer
Pseudostratified: Only one layer but looks like many layers

Question 4

What are the four types of cell shapes

Answer 4

Squamous: Thin, flat cells. Flattened/squashed nuclei.
Cuboidal: Cube shaped. Large round nuclei.
Columnar: Tall cells. Nuclei usually towards the base.
Transitional: Can change shape from a taller cell (columnar) to a flatter shape (cuboidal, squamous)

Question 5

Describe the function and location of simple squamous epithelium

Answer 5

Function: Diffusion (thin), Filtration (thin) and some secretion.
Location: Alveoli of lungs (quicker diffusion) and serous membranes of pleura (secretion of serous fluids).

Question 6

Describe the function and location of simple cuboidal epithelium

Answer 6

Function: Absorption (microvilli), Secretion (plump), and movement (cilia).
Locations: Kidney tubes (Absorption and secretion) and terminal bronchioles (cilia, movement).

Question 7

Describe the function and location of simple columnar epithelium

Answer 7

Function: Absorption, secretion and movement.
Location: Intestines (absorption and movement) and stomach (secretion of nutrients).

Question 8

Describe the function and location of transitional epithelium.

Answer 8

Function: Accommodates changes in fluid volume of the organ
Location: Urinary bladder, Ureter and the upper part of the urethra.

Question 9

What is a special characteristic of stratified squamous

Answer 9

Keratinised and non-keratinised cells. Keratin is a protein that makes cells more durable and longer lasting. Lots of layers to protect underlying tissue/cells from abrasian and damage.

Question 10

Function and location of stratified squamous

Answer 10

Function: Protection against abrasian and loss of water
Location of non-keratinised: Mouth, oesophagus, anus, vagina
Location of keratinised: Sole of feet, palms of hands. Skin.

Question 11

Function and location of stratified cuboidal

Answer 11

Function: Absorption (some have microvilli), Secretion (cube shaped) and protection (many layers).
Location: Ducts of sweat glands, ducts of salivary glands and developing ovum.

Question 12

Function and location of stratified columnar

Answer 12

Functions: Secretion (tall cell) and protection (many layers).
Location: Ducts of mammary glands, larynx and part of the male urethra.

Question 13

Describe pseudostratified epithelium

Answer 13

Single layer of column shaped cells with differing heights where some cells may not extend all the way to the surface. Nuclei are all over the place and cells are ciliated.

Question 14

Function and location of pseudostratified

Answer 14

Function: Secretion (column shaped) and movement (cilia).
Location: Pharynx and trachea (cilia carries mucus away) and male’s sperm carrying ducts (secretion for sperm maturation and cilia will carry sperm outside).