Intro: Epithelial Tissue/Cells

Question 1

What are 4 basic tissues?

Answer 1

1. Epithelial Tissue
2. Nervous Tissue
3. Connective Tissue
4. Muscular Tissue

*Composed

• ECM
• Polysaccharides
• Tissue Fluid

Question 2

What is Parenchyma?

Answer 2

1. Cells with specific functions for organs
2. Bulk of organs

Question 3

What are Stroma?

Answer 3

1. CT
2. Associated blood vessels and nerves
3. Supports parenchyma

Question 4

What 3 tissues Don’t Fit Into Any Basic Tissue Type?

Answer 4

1. Germ cells
2. Stria Vascularis of the Inner Ear
3. Synovial Membranes of Joint Capsules

Question 5

What are Sarcomas?

Answer 5

1. Malignancies that arise from Mesothelium and Endothelium

*Carcinomas

• Malignancies from lining epithelium/endothelium

*Adenocarcinomas

• Malignancies from Glandular Epithelium

Question 6

What are Mucous Membrane?

Answer 6

1. Mucosa
2. Lines lumen of organs
3. Consist

• Lining epithelium
• Lamina propria
• Basement membrane

Question 7

What Serous Membrane?

Answer 7

1. Serosa
2. Lines pleural, pericardial, and peritoneal cavities
3. Consist

• Mesothelium
• Supporting CT
• Basement membrane

4. Does NOT contain GLANDS

Question 8

What is Epithelial Tissue?

Answer 8

1. Defined by expression of TRANSMEMBRANE ADHESION MOLECULE E-CADHERIN
2. Nutrition from underlying CT
3. Function

• Skin: Protection from bacteria, chemicals, and excessive loss of water
• Kidneys: Excretion of waste products and reabsorption of material from urine
• Walls of Capillaries and Lungs: Diffusion of gas, liquid, and nutrients
• Air Passage: Removal of Dust
  
  • Type 1 and 2 Pneumocytes
• Small Intestine: Absorption of Digestive Food
• Circulatory System: Reduce friction from Blood and vessels
• Glands: Secretion (Enzymes, Hormones, Lubricating fluids)

Question 9

What is Pinocytosis?

Answer 9

1. Transport Ion-transporting cells
2. Tight Junctions present

Question 10

What is Myoepithelial Cells?

Answer 10

1. Contractile Epithelial Cells
2. Actin and Myosin filaments in cytoplasm
3. Located by

• Basal Lamina (part of basal membrane)
• Basal surface of Acinar Cells

4. Contraction

• Squeezes
  
  • Serous acinus and ducts

Question 11

What are Epithelial Cells?

Answer 11

1. Polarized
2. Apical present
3. Intercellular Junctions
4. Transmembrane proteins
   * Adhesion of molecules
5. Rest on Basal Lamina
   * Component of Basement Membrane

Question 12

What are Simple Epithelium?

Answer 12

1. Rest on Basement Membrane
   * One Cell Layer
2. Surface specialization
   * Cilia and Microvilli
3. Types

• Simple Squamous
  
  • Passive diffusion
  • Ex: Lung alveoli, Blood vessels, and Body Cavity
• Simple Cuboidal/Columnar
  
  • Highly Active
  • Lines secretory or absorptive surface (small intestines)
  • Function
    
    • Excretion
    • Secretion
    • Absorption

Question 13

What is Pseudostratified Epithelium?

Answer 13

1. Protection
2. Secretion of mucus (goblet cells)
3. Movement of mucus by Cilia

Question 14

What is Simple Squamous Epithelia?

Answer 14

1. Thinnest
2. Flat, Rounded, Centrally located
3. Nuclei
4. Function
   * Rapid Exchange by diffusion or filtration
5. Distribution

• Lungs (alveolar sac)
• Mesothelial lining of serous body cavities
• Loop of Henle
• Parietal layer of Glomerular (Bowman) capsule
• Lines Cardiovascular systems

Question 15

What are Endothelium?

Answer 15

1. Prevent blood cell interactions with Vessel Wall
2. Role

• Regulation of
  
  • Coagulation
  • Leukocyte adhesion
  • Vascular smooth muscle cell growth

Question 16

What are Simple Cuboidal Epithelia?

Answer 16

1. Cube-shaped
2. Nuclei
3. Function

• Filtration
• Secretion
• Absorption
• Excretion

4. Distribution

• Line Proximal and distal convulated tubules
• Thyroid glands
• Sweat glands
• Intercalated Ducts
• Bronchioles
• Surface of Ovary

Question 17

What are Pseudostratified Epithelia?

Answer 17

1. Single Layer cells
   * Not all cells reach surface
2. Cilitated
3. Function

• Protection
• Secretion of Mucus (goblet cells)
• Movement of mucus by Cilia

4. Distribution

• Nasal Cavity
• Trachea
• Bronchi
• Male sexual ducts

Question 18

What are Simple Coumnar Epithelia?

Answer 18

1. Rectangular in Shape
2. Cilia and Microvilli
3. Nuclei
   * Enlongated and basal
4. Function
   * Secretion and Absorption
5. Distribution

• Mucosal Lining of GIT
• Salivary glands
• Uterus
• Uterine Tube

*Ex: Bronchioles

• Ciliated columnar; movement of particles

Question 19

What is Stratified Squamous Epithelia?

Answer 19

1. Squamous flat
2. Highly Mitotic
3. Location
   * Areas of “Wear and Tear”
4. Keratinized (Stratum Corneum)

• Only in Epidermis
• Death cells impregnated with fibrous Keratin (cytoskelton protein)

5. Non-Keratinized or Mucous Type

• In Superficial cells
• Nucleated and Living
• Location
  
  • Cornea
  • Nasal opening
  • Esophagus
  • Vagina
  • Urethral opening

Question 20

What is Stratified Cuboidal Epithelia?

Answer 20

1. 2-3 Layers
   * Superficial layer
2. Distribution

• Excretory Ducts
  
  • Sweat glands
  • Salivary glands
  • Pancreas
  • Seminiferous tubules
  • Graafian follicles

Question 21

What are Stratified Columnar Epithelia?

Answer 21

1. Rare
2. Distribution

• Penile Urethra
• Large (Interlobular and interlobar) ducts of Salivary Glands
• Palpebral Conjunctiva (eye lids)

Question 22

What are Transitional Epithelium (Urothelium)?

Answer 22

1. Between
   * Stratified Cuboidal and squamous epithelia
2. Withstand

• Urine Toxicity
• High degree of Stretching

3. Relaxed State
   * Cuboidal; 4-5 cells thick
4. Stretched State
   * Squamous; 2-3 Cells thick
5. Superficial Cells

• Domed/rounded shape
• Umbrella Cells or Pillow Cells
• Distribution
  
  • Renal Calyces
  • Renal Pelvis
  • Ureter
  • Urinary Bladder