Bone Flashcards
Where does bone tissue occur?
In the different bones of the skeleton
Describe bone
Bone is a hard and rigid tissue
What does bone consist of that cartilage also consists of?
Living cells with large amounts of ground substance/matrix
What is bone impregnated with?
organic salts:
- calcium carbonate
- calcium phosphate
What other substances are present in bone in small amounts?
Small amounts of sodium and magnesium
What does the matrix of the cells making up the bone contain?
Numerous collagenous fibres and a large amount of water
What constitutes the organic (living) matter in bone tissue?
Collagen fibres together with the bone cells
What does dense, compact bone show under the microscope?
A definite and a characteristic pattern of arrangement
How is the ground substance of bone arranged?
In concentrated layers (lamellae) round the small canals which run parallel to the long axis (shaft) of the bone
What are the small canals which run parallel to the shaft of the bone called, and what do they contain?
These are called Haversian canals.
They contain a blood vessel, a nerve and a lymph vessel
What is each Haversian canal surrounded by?
Concentric layers of bone matrix (lamellae) and concentric rings of bone, forming cells (osteoblasts)
What are osteocytes?
Bone cells that have been completely surrounded by the hard bone matrix
Where are the osteocytes embedded?
The osteocytes are embedded in fluid-filled cavities within the concentric lamellae
What are the fluid-filled cavities in which osteocytes are embedded called?
These cavities are known as lacunae and occur at regular intervals in these concentric laters of bone tissue
To what and how are lacunae connected?
The lacunae are connected to one another to the Haversian canals by a system of interconnecting canals known as canaliculi
What are canaliculi?
A system of interconnecting canals
How and what forms a Haversian system?
each Haversian canal
+ its concentric lamellae
+ lacunae with osteocytes
+ canaliculi
forms a long cylinder (Haversian system)
What is the function of bone in relation to the skeleton?
The skeleton, which consists mainly of bone tissue, forms a supportive framework, giving shape and rigidity to the body
What is the function of bone in relation to movement?
The bone tissue forms a system of levers to which the voluntary muscles are attached
What is the function of bone in relation to protection?
It serves to protect the soft and delicate organs of the body such as the skull protecting the brain
What is the function of bone in relation to red blood cells?
Red blood cells are manufactured in the red bone marrow, which is situated in the spongy tissue at the ends of long bones
List some of the bone disorders
- osteoporosis
- arthritis
- rheumatoid arthritis
- rickets
What is osteoporosis?
Osteoporosis is the deterioration of vertebral supports
How does osteoporosis occur?
Osteoporosis occurs when bone density decreases and the body stops producing as much bone as it did before
