Chapter 4 vocab

Question 1

Tissues

Answer 1

Collections of specialized cells and cell products that performs specific functions

Question 2

Histology

Answer 2

Study of tissues

Question 3

Functions of Epithelial Tissue

Answer 3

1. Provide physical protection
2. Control permeability
3. Provide sensation
4. Produce specialized secretions

Question 4

Characteristics of epithelia

Answer 4

• Polarity
• Cellularity (cell junctions)
• Attachment (basement membrane)
• Avascularity (avascular)
• Regeneration

Question 5

Specializations of epithelial cells

Answer 5

1. Move fluids over the epithelium (protection)
2. Move fluids through the epithelium (permeability)
3. Produce secretions (protection and messaging)at

Question 6

Integrity of epithelia maintained by

Answer 6

1. intercellular connections
2. attachment to basement membrane
3. epithelial maintenance and repair

Question 7

Apical surface

Answer 7

Microvilli increase surface area and absorption

Question 8

Cell Adhesion Molecules (CAMs)

Answer 8

Transmembrane proteins that serve as support and communication (intercellular connections)

Question 9

Cell junctions

Answer 9

Form bonds with other cells or extracellular material

1. Gap junctions
2. Tight junctions
3. Desmosomes

Question 10

Gap Junction functions

Answer 10

• Allow rapid communication
• Cells held together by interlocking transmembrane proteins (connexons)
• allows small molecules and ions to pass
• coordinate contractions in heart muscle

Question 11

Tight junctions

Answer 11

• between two plasma membranes
• adhesion belt attaches to terminal web
• prevent passage of water and solutes
• keep enzymes, acids, and wastes in the lumen of the digestive tract

Question 12

Desmosomes

Answer 12

• CAMs and proteoglycans link opposing plasma membranes

- attachment to basement membrane (basal lamina and reticular lamina)

Question 13

Spot desmosomes

Answer 13

• tie cells together

- allow bending and twisting

Question 14

Hemidesmosomes

Answer 14

attach cells to basement membrane

Question 15

Classification of epithelia based on shape

Answer 15

• Squamous: thin and flat
• Cuboidal: square shaped
• Columnar: tall, slender rectangles

Question 16

Classification of epithelia based on layers

Answer 16

• Simple epithelium: Single layer of cells

- Stratified epithelium: Several layers of cells

Question 17

Simple squamous epithelium

Answer 17

Absorption and diffusion

Question 18

Mesothellum

Answer 18

lines body cavities (simple squamous)

Question 19

endothellum

Answer 19

forms inner lining of heart and blood vessels (simple squamous)

Question 20

stratified squamous epithelia

Answer 20

• Protects against mechanical stresses

- Keratin adds strength and water resistance

Question 21

simple cuboidal epithelia

Answer 21

• secretion and absorption

- glands and portion of kidney tubules

Question 22

stratified cuboidal epithelia

Answer 22

• relatively rare

- ducts of sweat glands and mammary glands

Question 23

transitional epithelia

Answer 23

• tolerate repeated cycles of stretching without damage
• Appearance changes as stretching occurs
• Found in urinary bladder

Question 24

simple columnar epithelia

Answer 24

• absorption and secretion

- Found in stomach, small intestine, and large intestine

Question 25

pseudostratified columnar epithelia

Answer 25

- typically have cilia | - found in nasal cavity, trachae, bronchii

Question 26

stratified columnar epithelia

Answer 26

- relatively rare | - provide protection in pharynx, anus, urethra

Question 27

Glands

Answer 27

Collections of epithelial cells that produce secretions

Question 28

Endocrine glands

Answer 28

- release hormones that enter bloodstream | - no ducts

Question 29

Exocrine glands

Answer 29

- produce exocrine secretions | - Discharge secretions through ducts onto epithelial surfaces

Question 30

Gland structure

Answer 30

- unicellular glands | - multicellular glands

Question 31

Goblet cells

Answer 31

- unicellular exocrine glands | - secrete mucin, mixes with water to form mucus

Question 32

Multicellular exocrine glands classified by...

Answer 32

1. Structure of duct 2. Shape of secretory portion of gland 3. Relationship between ducts and glandular areas

Question 33

Methods of secretion

Answer 33

1. Merocrine 2. Apocrine 3. Holocrine

Question 34

Merocrine secretion

Answer 34

released by secretory vesicles (exocytosis)

Question 35

Apocrine secretion

Answer 35

released by shedding cytoplasm

Question 36

holocrine secretion

Answer 36

- released by cells bursting, killing gland cells | - Gland cells replaced by stem cells