Locomotion and Movement
The act of changing place or position by one or more parts or by the entire body is termed as movement.
Some forms of movement exhibited by animals are protoplasmic streaming, movement by cilia, flagella and tentacles, movements by fins, limbs, wings, etc.
A voluntary movement which causes the animal to change its place is called locomotion.
Cells of the human body exhibit three main types of movements: amoeboid, ciliary, and muscular.
Muscle is a specialised tissue of mesodermal origin.
Special properties of muscle are: Excitability, contractility, extensibility and elasticity.
There are three types of muscles based on their location: Skeletal or striated, visceral or smooth or non-striated and cardiac.
Every organised skeletal muscle is made of a number of fascicles held together by a fascia.
Muscle fibre is the anatomical unit of muscle.
Each muscle fibre is made up of myofilaments or myofibrils.
The myofibrils are arranged in sections known as sarcomeres.
Myoglobin is a globular protein similar to haemoglobin. It is a red coloured pigment. Based on the amount of myoglobin which is present in skeletal muscles, skeletal muscles can be classified into red muscles and white muscles.
Some of the disorders of muscular system include: muscular dystrophy, myasthenia gravis.
All vertebrates have special hard structures making up the innermost scaffold of their body known as skeleton. It is made up of
bones. All bones in the body along with softer cartilages are known as the skeletal system.
Depending on their location skeletons are of two types- exoskeleton and endoskeleton.
Axial skeleton consists of vertebral column, skull and ribs. Whereas appendicular skeleton consists of girdle bones and limb bones.
Joint is a place of two or more parts. The joint acts as fulcrum on which the articulating parts move as levers.
Joints can be classified into fibrous joints, synovial joints and cartilaginous joints.
Some of the common disorders of joints include arthritis, gout, and osteoporosis.
Rheumatoid arthritis is a chronic autoimmune disease that causes inflammation and deformity of the joints.
Osteoporosis is a disease in which the bones become extremely porous hence they are more prone to fracture that heal slowly.