[C] 1.47 Metaplasia, pseudomateplasia

Question 1

Define metaplasia

Answer 1

Repair type: Change in the tissue type

• One type of differentiated tissue is replaced by another type of differentiated tissue
• Limited possibility of changing

Question 2

Metaplasia is only possible on which tissue types?

Answer 2

• Epithelial tissue to epithelial tissue
• Connective tissue to connective tissue

Question 3

Give the forms of metaplasia

Answer 3

• Direct
• Indirect

Question 4

Direct metaplasia

Answer 4

Unproved as of yet

Differentiated cells undergo transformation

Question 5

Indirect metaplasia: Summary & types

Answer 5

Multipotent cells replace degenerated tissue

Differentiate in a different way

• Prosoplasia (more differentiated)
• Anaplasia (less differentiated)

Question 6

Causes of metaplasia

Answer 6

• Cell damage (but under certain conditions)
  
  • Vit. A deficiency in poultry
  • Irritation of mucous membranes
  • F-2 toxins in the uterus
  • Bone tissue formation in a wound
  • Ossification of the left atrium

Question 7

Pseudometaplasia: Summary

Answer 7

• Appearances mimicking metaplasia
• Different kind of tissue in a certain place
• Originating from choristia

Question 8

Locations of pseudometaplasia with tissue type

Answer 8

• Tonsils → Cartilage
• Gastric mucosa → Oseophagus islets
• Lung → Kidney tissue
• Spinal cord → Portions of intestines
• Vaginal epithelium → Columnar epithelium

Question 9

Allomorphia & dysmorphia

Answer 9

• Change in shape but not in type
• Reversible
• Examples:
  
  • Thyroid gland
    
    • Epithelial cells lining the follicles
  • Lung
    
    • Epithelial cells lining the alveoli