ANA300Y1 Lecture Notes - Lecture 44: Tumor Suppressor Gene, Stratified Squamous Epithelium, Metaplasia
Document Summary
By the end of this unit you should be able to: Define and describe the terms hyperplasia, hypertrophy, atrophy, metaplasia and dysplasia: hyperplasia. An increase in the cell number; takes place if cell population is capable of replication (it results when the cells of a tissue are stimulated to undergo mitosis) Main mechanism causing increased size in tissues consisting of stable and labile cells tissues showing pathologic hyperplasia are at increased risk of neoplastic transformation (becoming cancerous) Physiologic hyperplasia includes hormonal hyperplasia (exemplified by proliferation of glandular epithelium of female breast at puberty/during pregnancy) and compensatory hyperplasia (hyperplasia that occurs when a portion of the tissue is removed or diseased) Enlarged by an increased amount of structural proteins and organelles (increase in amount of cytoplasm and numbers of cytoplasmic organelles) Only refers to a tissue or organ which was previously normally formed; organs can be underdeveloped (hypoplasic) or completely undeveloped (aplastic)
