Human Skeleton
Describe Facial Bones
enclose the front of the brain and form openings for the eyes, the nasal cavity, and the oral cavity
Cervical Area
forms neck and supports the skull
What does the skeletal system do for the body?
it provides a strong framework for the body, gives it its basic shape, permits us to stand upright, supports and holds in place soft internal organs, and protects fragile organs.
Lumbar Section
makes up the lower back
Fontanelles
membrane-filled spaces between the bones
Describe the base of the skull
much thicker and stronger than the sides and top and has many openings for the nerves blood vessels and tubes to pass through.
Skull
protective case for the brain and organs of sight, taste, smell, hearing, and balance, it rests and pivots on upper end of vertebral column
Vertebral Column "Spine"
stack or 33 irregular vertebrae or bones, all tied tightly together by ligaments, forms the strong flexible column known as the "spine"
Fill in the blank: The skeletal system provides a ______ _________ for the body.
strong framework
What are the skull's two main parts?
the cranium (or brain case) and the facial bones
What does strong elastic tissue make up?
the ligaments and tendons
What does Cartilage Tissue form?
the nose, larynx, trachea, bronchial tubes, and the outer ear
What does the Axial Skeleton consist of?
the skull, the vertebral column, the sternum, and the thorax
Thoracic Region
the thoracic region, together with the ribs, forms the thorax or chest cavity
Describe the Mandible
(jawbone) only movable bone in the skull
How many bones in the human body?
206 bones
How many regions can the Vertebral Column be divided into?
5
Short Bones
[kneecap, wrist, ankle] shaped like irregular cubes, spongy with a covering of compact tissue.
Long Bones
[legs, arms, toes, and fingers] strong shafts made of compact tissue. ends are large and consist of spongy tissue covered with compact tissue. slightly curved so they can absorb shock.
Flat Bones
[skull, ribs, sternum, hips, and scapula] broad flat plates of spongy tissue sandwiched between two layers of compact tissue. they protect organs and are anchor points for the muscles.
Irregular Bones
[vertebrae and facial bones] irregularly shaped, different proportion of spongy to compact tissue from bone to bone.
What do bones provide?
a firm anchor for skeletal muscles and produce red blood cells in their marrow cavities
Where is the largest Fontanelle and when does it close?
between the parietal and frontal bones, closes after about eighteen months
Coccyx
bottom four vertebrae where our tail should have been
Examples of fragile organs protected by the skeletal system:
brain, lungs, and heart
What happens as a fetus develops?
cartilaginous membranes of the cranium turn to bone (OSSIFY). At birth, ossification isn't complete and fontanelles remain as "soft spots"
What are the 5 regions of the spine?
cervical area, thoracic region, lumbar section, sacrum, coccyx
Sacrum
consists of 5 vertebrae fused into one triangular bone and forms part of the hip