A: Histology of connective tissue Flashcards
Functions of connective tissue
- Structure
- Protection
- Storage
- Transportation
- Defense
Fibroblasts
- Flat cells with elongated nuclei.
- Produce fibres + ground substance
- Help in wound healing (mesenchymal cells develop into fibroblasts and enter a wound site. They secrete ground substance + fibres to make a collagenous scar which replaces damaged tissue).
What are the dark blue things
Fibroblasts
Mast cells
- Common beneath membranes + along small blood vessels
- In their cytoplasm there are granules with histamine (causes capillaries to leak, causing oedema which dilates blood vessels causing warmth + redness) and heparin (inhibits blood clotting)
Identify
Mast cells
Plasma cells
- Derived from B cells
- Large, granular + round nucleus
- Secrete specific antigens.
Identify
Plasma cell
Adipocytes
- Synthesise + store fat
- Release cytokines
White adipocytes
large lipid droplets push nucleus to edge of cell
Brown adipocytes
found in newborn mammals, used for thermoregulation. Are smaller, central nucleus + many small lipid globules.
Identify
White adipocyte
Identify
Brown adipocyte
Collagen
- Strong + inelastic
- Produced by fibroblasts
- Tropocollagen (3 collagen a-fibres) come together to make collagen microfibrils which make collagen fibres
What is E, L and Ma?
Elastin
Collagen
Mast cells
Ehlers-Danlos syndrome
Mutated gene forming abnormal collagen.
- Hypermobile ligaments
- Hyperelastic skin bruises easily
Osteogenesis imperfecta
- Mutation in gene for collagen synthesis –> abnormal collagen
- Extremely fragile bones
- More likely to be deaf.
- Blue sclera
Elastin fibres
- Branched fibres, can stretch + recoil
- Synthesised by fibroblast
- Made of protein elastin + fibrillin (which forms scaffolding for elastin)
Marfan’s syndrome
- Mutation in fibrillin gene
- Makes skeleton tall + thin with arachnodactyly
- Risk of developing aortic dilation or aortic aneurysm
- Leaky heart valves
- Myopia in eyes
Reticular fibres
- Fine, highly branched collagen fibres
- Form structural framework
- Found in lymph nodes + spleen
Ground substance:
- Semi-fluid gel in between cells + fibres
- Made of glycosaminoglycans (polysaccharides), proteoglycans (bind water, giving gel-like properties), water and salt
- Size of spaces between glycosaminoglycans determines permeability of tissue
- Delays spread of infection through tissue
Types of general connective tissue
- Loose connective tissue: low density of fibres
- Dense connective tissue: dominated by fibres
Dense connective tissue:
Dominated by fibres
Dense regular: fibres run parallel
Dense irregular: fibres have no clear orientation
Identify
Areolar connective tissue
Loose connective tissue:
Low density of fibres
- Areolar
- Adipose
Identify
Adipose loose connective tissue
Identify
Regular dense connective tissue
Identify
Irregular dense connective
Identify
Elastic dense connective tissue
Identify
Mesenchymal
Identify
Reticular connective tissue
Identify
Reticular connective tissue
Identify
Brown adipose tissue
Identify
Mesenchymal connective tissue
