Wk 4 Flashcards
Connective Tissues
What are connective tissues (CT)?
Are cells that are widely spaced and separated by extracellular matrix (ECM).
- Usually highly vascularised (except tendons, ligaments, cartilage)
- Has a nervous supply
What are the functions of CT?
- Support
- Protection
- Insulation (exterior environment)
- Storing energy reserves (fats)
- Endocrine
- Transportation
What are the CT cell types?
- Immature cells
- Mature cells
What are immature cells?
Name ends with ‘blast’, secrete the ECM (lay down the fibres that create CT).
- Fibroblasts (dense, loose, reticular)
- Chondroblasts (cartilage)
- Osteoblasts (bone)
What are mature cells?
Name ends with ‘cyte’, maintain cell environment.
- Fibrocytes (dense, loose, reticular)
- Adipocytes (adipose tissue)
- Chondrocytes (cartilage)
- Osteocytes (bone)
- Erythrocytes (blood)
What are cell types present in CT proper?
- Fibroblasts, fibrocytes
- Reticular cell (type of fibroblast)
- Adipocytes (store fat)
- Macrophages (eat things that shouldn’t be there)
- Plasma cells (secrete antibodies)
- Mast cells (produce histamine)
- Leukocytes (white blood cells)
What is Extracellular Matrix (ECM)?
Located between cells and fibres it contains protein fibres and ground substance. Provides CT with its properties.
Structure can be:
- Gelatinous
- Fluid
- Semifluid
- Calcified
Function (dictated by structure):
- Supports and binds cells together
- Allows substances to be exchanged pass to and from blood
- Stores water (not bones)
What are protein fibres?
Secreted by the cells.
- Collagen
- Elastic
- Reticular
What is ground substance?
- Water and organic molecules
- Supports the cells
- Allows exchange of substances
What are the types of fibres present in CT proper?
- Collagen (strength, resistance to tension)
- Elastic (strength and stability, stretched & recoiled)
- Reticular (contains collagen but thinner and branched, strength & support)
What is the common origin of CT?
Mesenchyme (loosely organised animal embryonic CT).
What are the types of CT?
- CT proper (connects tissue and organs together)
- Supporting CT
- Fluid CT
What are the types of CT proper?
- Loose (Areolar) CT - fewer fibres
- Dense CT - more fibres
What is loose CT?
Fibres are arranged “loosely” between cells.
What are the types of loose CT?
- Adipose - adipocytes
- Areolar - fibroblasts, immune cell
- Reticular - fibroblasts