Movement system in human

This movement system involves two component of body systems:
- Skeletal system
- Muscular system
These two system will be discussed briefly before you are asked to identify those two system in detail
The mechanism of how these two systems generate movement in human body will also be discussed


Skeletal system

The objective of this chapter:
– The students should be able to:
List the 5 functions of the skeletal system
Label a diagram of a long bone and describe the microscopic structure of a bone
Describe the division of the skeletal system
List and describe the bones of axial skeleton and identify each on a diagram or skeleton
List and describe the bones of appendicular skeleton and identify each on a diagram or skeleton
Compare the main types of joints, and describe the structure and functions of a diarthrosis

Functions of the skeletal system

It support the body by serving as a bony framework for the other tissues and organs
It protect delicate vital organs, for examples:
– The skull surround and protect the brain
– The ribs protect the lung and heart
Bones serve as levers that transmit muscular forces
– Muscles are attached to bones by bands of connective tissue called tendons
– When muscles contract, they pull on bones, and in this way they move parts of the body
– Bones are held together at joints by bands of connective tissue called ligaments.
– In this case, Most joints are moveable
The marrow within the bones produces blood cells
Bones serve as bank for the storage and release of minerals, such as calcium and phosphorous

Long bones

The main shaft of the long bones is known as its diaphysis (Fig 4.1)
The expanded end is called epiphysis
The metaphysis (a disc of cartilage located between diaphysis and epiphysis) is found in children
The metaphysis disappear at maturity, becoming a vague epiphyseal lines
Within the long bones is a central marrow cavity which is lined by thin layer of cell (endosteum)
This is filled with fatty connective tissue called the yellow bone marrow


Two types of bone tissue

The compact and the spongy bones
– Compact bones
Note
- The structure is very dense and
hard
-characterized by harvesian sys-
tem (see fig)

– Spongy bone:
Found within the epiphysis
Makes up the inner part of the wall of the diaphysis
Consists of a network of thin strands of bone
The space within the spongy bone is filled with bone marrow:
– Red marrow (found in certain bones): produces blood cells
– Yellow marrow: consists mainly of fat cells



The skeleton division

Axial skeleton consists of:
– The skull
– Vertebral column
– Ribs
– Sternum
Appendicular skeleton consist of:
– Upper and lower limbs (Arms and Legs)
– Shoulder girdle
– Pelvic girdle (except the sacrum)

The skull (the bony framework of the head

This is divided into:
– Cranial bones (consists of 8 cranial bones that enclose the brain)
– Facial bones (consists of 14 bones) Fig. 4.5 – 4.8
Most of the bones of the skull are joined by immoveable joint called sutures:
– The sagittal suture is the joint between the two parietal bones
– The coronal suture joins the parietal bones to the frontal bone
– The lambdoidal suture is the joint between the parietal bones and the Occipital bone


The vertebral column


Support the body and bear its weight
Consists of 24 vertebrae and 2 fused bones (the sacrum and coccyx (Fig 4.9)
The region of vertebral column are:
– The neck (cervical) composed of 7 vertebrae
– Chest (Thoracic) consists of 12 vertebrae
– Back (Lumbar) consists of 5 vertebrae
– Pelvic (Sacral) consist of 5 fused vertebrae
– Coccygeal also consists of fused vertebrae
Certain structural feature of vertebrae is shown in