Tissue Types and Cell Changes Flashcards
Review Basic Science from Week 1
What are the 4 types of tissue?
- Epithelial (covers, secretes)
- Connective (support, protect, energy storage)
- Muscle (movement)
- Nervous (transmission and coordination
Tissue
Group of cells with similar structure, function, and embryonic origin.
Major Functions of Epithelium? (3)
- Protective Barrier
- Regulates exchange (absorption and diffusion)
- Synthesizes and secrete glandular products.
Brush Border
Microvilli used for absorption. Lines columnar epithelia (ie. large intestine)
“Umbrella/dome” shaped cells are found in…?
Transitional epithelia: Urothelium (bladder, ureters)
What are Cilia?
Cytoplasmic projection of membrane, “hair-like,” and MOTILE (fallopian tubes and respiratory airways)
What are Microvilli?
NON-MOTILE Cytoplasmic projections that increase membrane surface area (absorptive ability).
What are Goblet Cells?
Modified columnar epithelial cells that are meant to secrete mucin.
Keratin
Tough non-living surface layer of skill (typically external)
Cellular Adaptation
Reversible and structural cellular changes in response to environmental changes
Metaplasia
Change in the cell phenotype.
Cachexia
Weakness and wasting away of the body due to severe chronic illness.
What are the 4 main pathways to abnormal cellular accumulation?
- Poor removal of endogenous substance
- Inadequate/abnormal folding/packaging/transport
- Inability to degrade metabolite due to genetic enzyme deficiency
- Poor removal/transport of exogenous substance
Steatosis
Abnormal accumulation of triglycerides within parenchymal cells (often liver)
Dystrophic Calcification
Calcification occurring in degenerated/necrotic tissue.
Metastatic Calcification
Calcification occurring in normal tissue. Due to elevated serum calcium.
Main Causes of Cell Injury (6)
- Oxygen Deprivation
- Nutritional Imbalance
- Physical/Chemical Agents/drugs
- Genetic Derangements
- Immunologic Reactions
- Infectious Agents
Necrosis
An UNREGULATED form of cell death resulting from sever damage to cell membranes and loss of ion homeostasis. (always pathologic)
Apoptosis
Programmed cell death. (Can be pathologic or physiologic)
Caseous Necrosis
Form of cell death in which the tissue maintains a cheese-like appearance. (Common in TB infection)
Fat Necrosis
Necrosis of fatty/adipose tissue. (Commonly due to release of pancreatic enzymes; pancreatitis)
4 Mechanisms of Cell Injury?
- Mitochondrial Damage (A or N)
- Calcium Entry (A or N)
- Membrane Damage (N)
- Protein Misfolding (A)
What is a caspase and what pathways (2) does it play a role in?
A caspase is a cysteine-aspartic protease. It plays a roll in both mitochondrial (intrinsic) and death receptor (extrinsic) apoptotic pathways.
What is Autophagy?
Cells will eat themselves/their own components. (Fusion with lysosomes)
Keratinization
The process in which the cytoplasm of the outermost cells of the mammalian epidermis is replaced by keratin
Dysplasia
Abnormal development of cells within tissues or organs
Neoplasia
Uncontrolled, abnormal growth of cells or tissues in the body. (abnormal growth itself is called a neoplasm)
Major Types of Connective Tissue? (3)
- Dense CT (Tough & supportive; ie tendons)
- Areolar CT (Biologic packing/wrapping)
- Specialized CT (blood, bones, etc.)
Causes of Acute Inflammation
- Necrosis
- Foreign Substance
- Infections
- Immune Reactions
- Endogenous Substances
