Anatomy 10 - Connective Tissue Flashcards
Connective tissue consists of cells embedded in
Large quantities of extracellular matrix
The extracellular matrix is composed of
Protein fibres, amorphous ground substance and tissue fluid
What are the two categories of connective tissue
Soft connective tissue and hard connective tissue
Examples of soft connective tissue
Tendons, ligaments, mesentery, stroma of organs and dermis of skin
Examples of hard connective tissue
Bone and cartilage
How is the type of connective tissue determined
By the type and relative amount if cells and the extracellular matrix
Functions of connective tissue
Space filler, mechanical support, attachment, protection, highway for nutrients and innervation, fat store, calcium store and the site of many immunological defence reactions
What are the resident cells of connective tissue
Fibroblasts, adipose cells, osteocytes and chondrocytes
What are osteocytes
The cells of bones
What are chondrocytes
The cells of cartilage
What do fibroblasts produce/maintain
The extracellular matrix
What cell is involved in tissue repair
Fibroblasts
Types of fibres found within the extracellular matrix
Reticular and elastic fibres
What is ground substance
An amorphous, space occupying material made of huge unbranched polysaccharide molecules called glycosaminoglycans (GAGs)
What are GAGs bound to
Protein cores
What is a GAG bound to a protein core called
Glycoprotein
What is the function of adipose cells
Release fatty acid into the bloodstream to provide energy for other cells
Most common type of connective tissue
Loose CT
Characteristics of loose CT
Loosely packed fibres separated by abundant ground substances
Characteristics of dense CT
It is made up of densely packed bundles of collagen fibres
If the fibres of dense CT are aligned it is known as
Dense regular CT
Example of dense regular CT
Tendon
If in dense CT the fibre bundles run in many directions it is known as
Dense irregular CT
Example of dense irregular CT
Dermis of the skin
Characteristics of cartilage
It is semi-rigid, consists of scattered cells surrounded by an amorphous appearing extracellular matrix, it is deformable, permeable, cells are nourished by diffusion and they grow appositional and interstitially
Characteristics of bone
It is rigid, non-permeable, the cells within the bone are nourished by blood vessels that provide the matrix and they grow appositionally only
Functions of bone
Provide support, act as levers for movement, protection, calcium store and the site of haemopoiesis
What are the three types of cartilage
Hyaline, elastic and fibrocartilage
Where is hyaline cartilage found
Articular surfaces, tracheal rings, costal cartilage, epiphyseal growth plates and is the precursor to bone in the foetus
What is found in the extracellular matrix of elastic cartilage
Elastic fibres
Where is elastic cartilage found
In the pinna of the ear, epiglottis and auditory tube
What is fibrocartilage made up of
Dense regular CT, islands of cartilage cells and cartilage matrix
Where is fibrocartilage found
In the intervertebral discs, where tendons insert into bones and in the pubic symphysis
Cartilage surrounded by connective tissue is called
The perichondrium
What are the layers of the perichondrium
An outer layer of dense CT and associated fibroblasts
An inner chondrogenic layer
What does the outer layer of the perichondrium provide
Support
What does the inner layer of the perichondrium provide
It supplies nutrients to the whole of the cartilage
What is bone comprised of
Water, collagen, non-collagen proteins and calcium hydroxyapatite crystals
What do osteoblasts secrete
Collagen, GAGs, proteoglycans and other organic compounds
What are the secretions of the osteoblasts collectively known as
Osteoid
Function of osteoblasts
Bone forming cells found on the surface of developing bone
What are osteocytes
Bone cells trapped within the bone matrix
What are osteoclasts
Large, multinucleated cells found on the surface of bone
Function of osteoclasts
Bone reabsorption
What are osteoprogenitor cells
They are located on the surface of bones and serve as a pool of reserve osteoblasts
Inactive periosteum
No bone is being formed
Active periosteum
New bone is being formed
What happens to osteoprogenitor when new bone is being formed
They proliferate and differentiate into osteoblasts
What is the endosteum
A thin vascular membrane of connective tissue that lines the surface of bony tissue
Functions of the endosteum
Repair, remodel and grow bone
