S2) Connective and Adipose Tissues Flashcards
Describe 4 functions of connective tissue
- Connects cells to form tissues, connects tissues to form organs and connects organs to form the body
- Defence against infection (blood, lymph, fixed and wandering cells)
- Wound healing (macrophages, fibroblasts, myofibroblasts)
- Storage (adipose tissue)
What are the 3 components of Connective Tissue Proper?
- Cells
- Fibres
- Ground Substance
Identify and describe the 3 types of fibre in connective tissue
- Collagen – flexible with high tensile strength
- Reticular – provide a supporting framework/sponge
- Elastin – allows tissues to recoil after stretch or distension
Describe the properties of ground substance in connective tissue
- Viscous, clear substance with a high water content
- It is composed of proteoglycans
What is a proteoglycan?
A proteoglycan is a large macromolecule consisting of a core protein to which glycosaminoglycans (GAGs) are covalently bound
What is an extracellular matrix?
The extracellular matrix is the complex extracellular structural network that consists of ground substance and fibres
Distinguish between the structure of loose and dense connective tissue
- Loose:
I. Many cells
II. Sparse collagen fibres
III. Abundant ground substance
- Dense:
I. Few cells, nearly all fibroblasts
II. Many collagen fibres
III. Little ground substance
Where can loose connective tissue be found?
- Located beneath epithelia (to facilitate diffusion)
- Associated with epithelium of glands
- Located around small blood vessels
Describe the strategic location of the connective tissue
It is located at the sites where pathogens that have breached an epithelial surface and can be challenged and destroyed by the cells of the immune system
Identify two examples of loose connective tissue in the body
- Superficial layer of the dermis in the skin
- Submucosa of the colon
Describe the structure and function of dense regular connective tissue
- Structure:
I. Collagen fibres are arranged in parallel bundles and are densely packed
II. Fibroblasts are between the bundles
- Function: designed to withstand stress in a single direction
Where is dense regular connective tissue found?
- Tendons
- Ligaments
- Aponeuroses
Describe the structure and function of dense irregular connective tissue
- Structure:
I. Collagen fibres are arranged in bundles orientated in various directions
II. Fibroblasts are between the bundles
- Function: designed to withstand stress in multiple directions
Where is dense irregular connective tissue found?
- Submucosa of intestine
- Deep layers of dermis
What do tendons do?
Tendons connect muscles to bones