Connective Tissue Principles

Question 1

What are the constituents of general connective tissue?

Answer 1

• Cells
• Fibres ( varying amounts of collagen, elastic, reticular)
• Ground substance

Question 2

Describe the makeup of the ground substance

Answer 2

• High water content

- Proteoglycans

Question 3

What is the role of hyaluronic acid in ground substance?

Answer 3

bound to proteoglycans via link proteins to form giant macromolecular structure. gives cartilage its strong, flexible properties

Question 4

How does loose connective tissue differ from dense connective tissue?

Answer 4

Dense connective tissue has fewer cells and a higher collagen content, with less ground substance. Loose connective tissue plays a bigger role in diffusion.

Question 5

Where is loose connective tissue located?

Answer 5

• beneath epithelia to facilitate diffusion and associated with epithelia of glands
• also around small blood vessels

Question 6

What are the differences between dense regular and irregular connective tissue?

Answer 6

Regular- Collagen fibres are arranged in parallel bundles and are densely
packed. Between the bundles are fibroblasts. Designed to withstand stress in a single direction

Irregular- Collagen fibres are arranged in bundles orientated in various directions. Between the bundles are fibroblasts – Designed to withstand stress in multiple directions

Question 7

Where is dense regular connective tissue found?

Answer 7

Seen in tendons, ligaments and aponeuroses

Question 8

Where is dense irregular connective tissue found?

Answer 8

Deep layer of dermis, submucosa of intestine

Question 9

What cells are commonly found in connective tissue?

Answer 9

Fixed:

– Fibroblasts (and myofibroblasts)
– Melanocytes
– Mast cells
– Macrophages
– Adipocytes
– Mesenchymal ‘stem cells’ • 

Wandering immune cells, including:

– Leucocytes
– Plasma cells
– Monocytes
– Eosinophils
– Basophils

Question 10

What is the function of fibroblasts?

Answer 10

Synthesise and secrete ground substance and fibres. They are also important in wound healing.

Question 11

What are mast cells?

Answer 11

Mast cell cytoplasm contains abundant granules

These granules contain Histamine (increases
blood vessel wall
permeability), Heparin (an
anticoagulant) and substances that attract
eosinophils and
neutrophils. Mast cells become coated with Immunoglobulin E (IgE), molecules which specifically bind allergens. When an allergen cross-links these surface-bound IgE molecules, the contents of the granules are all rapidly released from the cell.
The secretions of the granules can result in immediate hypersensitivity reactions, allergy and anaphylaxis.