The Skeletal System Flashcards
A ___ is an organ made up of several different tissues working together: osseous, cartilage, dense CT epithelium, adipose tissue and nervous tissue. The entire framework of bones and their cartilages constitute the ___ system.
Bone; skeletal
List the 6 functions of bone tissue
Support, protection, assist in movement, mineral homeostasis, blood cell production, triglyceride storage.
How does bone tissue support the body?
Bones support the soft tissues and provide attachment sites for muscles, thereby serving as the structural framework for the body.
Describe how bone tissue protects the body.
Many of the body’s internal organs are protected by bony coverings.
Describe how the bone tissue assists in movement.
Bones assist skeletal muscles in producing movement.
Describe how bone tissue contributes to mineral homeostasis.
Bones store and release several minerals, especially calcium and phosphorus, to help maintain mineral homeostasis.
Describe how bone tissue contributes to blood cell production.
Hemopoesis, blood cell formation, occurs in the red marrow of bones
Describe how bone tissue contributes to triglyceride storage.
The yellow marrow of adult boned serves as a site of triglyceride storage.
Long bones
Consist of a shaft with 2 ends. Ex: the femur and humerus
Short bones
Are cube-like. Ex: carpals and tarsals
Flat bones
Are thin and usually curved. Ex: skull bones and ribs
Irregular bones
Are not long, short or flat. Ex: vertebrae
A typical long bone consists of the following 7 parts:
Diaphysis, epiphysis, metaphysis, articular cartilage (hyaline cart.), periosteum, medullary cavity (marrow cavity), and the endosteum.
The __ is the shaft of the long bone.
Diaphysis
The __ are the ends of the bone.
Epiphyses
The __ are the areas between the epiphysis and diaphysis and include the epiphyseal plate in growing bones.
Metaphyses
__ __ (__ __) at the ends of the bones reduces friction and absorbs shock at freely moveable joints.
Hyaline cartilage (articular cartilage)
The __ is a CT that covers the surface of the bone; it contains osteogenic cells, protects bone; it contains osteogenic cells, protects bone, assists in fracture repair, helps nourish bone tissue and serves as an attachment point for ligaments and tendons.
Periosteum
The space within the diaphysis is the __ __.
Marrow cavity (medullary cavity)
__ marrow is the site of blood production.
Red
__ marrow is the site of fat storage.
Yellow
The __ is the lining of the medullary cavity.
Endosteum
Bone (osseous) tissue consists of widely separated cells surrounded by large amounts of matrix. The 4 principal types of bone cells are the following:
Osteoprogenitor, osteoblasts, osteocytes, and osteoclasts.
Osteoprogenitor
Are precursor cells
Osteoblasts
Are bone building cells
Osteocytes
Are mature bone cells, the principal cells of bone tissue
Osteoclasts
Are derived from monocytes and serve to break down bone tissue
The __ of the bone contains inorganic salts, primarily hydroxyapatite and some calcium carbonate and collagen fibres.
Matrix
A __ bone is covered by __ __ at its proximal and distal epiphyses and by periosteum around the remainder of the bone
Long; articular cartilage
Which part of a bone reduces friction at joints?
The articular cartilage
Which part of a bone produces blood cells?
Red bone marrow
Which part of a bone lines the medullary cavity?
The endosteum
__ lie in lacunae arranged in concentric circles around a central canal in compact bone and in lacunae arranged irregularly in the trabeculae of __ bone
Osteocytes; spongy
The process of __ occurs only in the presence of __ fibres.
Calcification; collagen
As people age, some osteonic canals may become blocked. What effect would thus have on the osteocytes?
Because the central canals are the main blood supply to the osteocytes, their blockage would lead to death of osteocytes.
Compact bone is arranged in units called __ or __ __. Osteons contain blood vessels, lymphatic vessels, nerves and osteocytes, along with calcified matrix.
Osteons or Haversian systems
__ are aligned in the same direction along the lines of stress. The lines can change as the __ of the bone change.
Osteons; stresses
The process by which bone forms is called __
Ossification
__ __ involves the formation of bone within the mesenchyme arranged in sheet-like layers that resemble membranes.
Intramembranous ossification
During __ __ bone gradually replaces a cartilage model.
Endochondral ossification
Spongy (cancellous) bone does not contain __.
Osteons
Spongy bone consists of __ (columns or beams of bone), which surround many red-marrow-filled spaces.
Trabeculae
Which bones of the body develop by intramembranous ossification?
The flat bones of the skull, mandible, and part of the clavicle
Which structure signals that bone growth in length has stopped?
The epiphyseal lines
__ bone forms most of the structure of short, flat and irregular bones; and the epiphyses of long bones. __ bone is light and supports and protects the red bone marrow.
Spongy; spongy