The skeletal system is comparable to the structure of a building; it gives shape to and supports the structures and organs that make up the body.
It is divided into two main parts:
– Axial skeleton: It is composed of the human skull, vertebral column and thorax. It consists of 87 bones.
– Appendicular skeleton: It is consists of the upper (arms and hands) and lower extremities (legs and feet), as well as the pelvis and shoulders. It is made up of 130 bones.
Bones begin to develop by the eighth week of embryonic life. There are two types of osseous tissues: compact or cortical and spongy bones.
Muscles are powerful structures that allow humans to have an active life and be able to walk, talk, stand up and grab objects, among thousands of other activities.
They are also important in providing support for and protection to internal organs.
Three types of muscular tissues can be distinguished on the basis of function and physical characteristics:
– Skeletal muscles: they are also known as voluntary muscles and allow us to move.
– Smooth muscles: we do not have control over smooth muscles; they are found in internal organs.
– Cardiac muscle: a type of muscles that is only found in the walls of the heart and allows this organ to contract