L7 Connective Tissue Flashcards
Connective tissue is derived from which embryonic layer?
A) Ectoderm
B) Mesoderm
C) Endoderm
D) Any of the above
B) Mesoderm
What are the three basic components of connective tissue?
- Specialised cells (e.g. fibroblast, osteocyte…)
- Protein fibres (e.g. collagen, elastin, reticulin…)
- Ground substance
What is mesenchyme?
Undifferentiated embryological connective tissue
Does all of the mesenchyme develop into differentiated tissue during the embryological period, or does anything persist beyond this period?
Some persists, e.g. fibroblasts around blood vessels for repair; umbilical cord
How is connective tissue classified?
- Embryonic
- Proper
- Cartilage
- Bone
- Vascular
Proper connective tissue can be categorised into 6 sub-types. What are they?
Loose Dense Regular Dense Irregular Elastic Reticular Adipose
Loose Connective Tissue
Binding and packing
Flexible - strength in all directions
e.g. skin to underlying muscle, surrounds blood vessels and nerves
Dense Regular Connective Tissue
Densely packed collagen fibres parallel to direction of force
e.g. tendons and ligaments
What type of tissue are tendons and ligaments? (be specific)
Dense regular connective tissue
Dense Irregular Connective Tissue
Densely packed collagen fibres, interwoven.
Strength in all directions
e.g. dermis of skin, submucosa of GI tract
Elastic Connective Tissue
Elastic fibres that can stretch 1.5x and return to their shape
Elastic fibres are irregularly arranged and yellow
e.g. walls of large arteries; portions of larynx, trachea, and bronchial tubes
Reticular Connective Tissue
Network of woven reticular fibres in a jelly-like matrix
e.g. Forms framework of organs such as liver and spleen
Adipose Connective Tissue
Cells store fat droplets and swell
Acts as a food reserve, protects organs, insulates
e.g. hypodermis of skin, surface of heart, breast, surrounds joints
What cell type is found in cartilage?
Chondrocyte
What are the three types of cartilage?
Hyaline
Elastic
Fibrocartilage
Where is fibrocartilage found?
Pads within knee joint; between pubic bones of pelvis; intervertebral discs
What are the functions of fibrocartilage?
Resists compression; prevents bone-bone contact (wear); limits relative movement
Where is elastic cartilage found?
Auricle of external ear; epiglottis; auditory canal; cuneiform cartilages of larynx
What are the functions of elastic cartilage?
Provides support but tolerates distortion without damage and returns to original shape
Where is hyaline cartilage found?
Between tips of ribs and bones of sternum; covering bone surfaces at synovial joints; supporting larynx (voice box), trachea, and bronchi; forming part of nasal septum
What are the functions of hyaline cartilage?
Provides stiff but somewhat flexible support; reduces friction between bony surfaces
What gives bone its hardness?
Calcium phosphate
What are the two types of bone?
- Compact or dense (hard outer layer)
- Spongy or cancellous (porous, vascular inner layer)
What are the three cellular components of vascular connective tissue?
Vascular connective tissue = blood
- Erythrocytes
- Leukocytes
- Thrombocytes (platelets)
