Muscular System (Part-I)

Introduction: Locomotion is important to all organisms for various purposes like to find food, to mate, to escape from predators, for survival purpose, etc. and altogether, they influence in locomotive organ evolution process in animals. Locomotive organs are different in nature from one species to other. Muscles play important role in movement of the animals. In higher animals along with muscles, bones also associate for the movement. Animal movements can differentiate as walk, run, swim, fly, crawl and jump. Bacterial movement can classify as flagellar, spirochaetal and gliding movement. Single cell organisms also show crawling like movement often called amoeboidal movement as well as they show cillary movement, flagellar movement. Nature of movement is different in plants in which roots, branches, leaves move in response to environmental abiotic factors but overall the plant is non-movable. Here we discuss the different types of locomotion or movement and their mechanisms briefly.
Definition: Locomotion can defined as an ability to move from one place to another.
The organs which helps for the locomotion is called as locomotive organs. Ex: limbs, flagella, cilia, etc.
Locomotion in single cell organisms
Prokaryotic and eukaryotic single cell organism do movement for their survival, growth and reproduction.
Bacterial movements                                                                                     
Bacteria are single cell prokaryotic organisms. They show three different types of movements. They are

1. Flagellar movement
2. Spirochaetal movement and
3. Gliding movement.

Mechanism of these movements are partially understood.

Flagellar movement
Bacteria can move in liquids with help of flagellum. Depends on number of flagella, arrangement over cell surface, bacteria were named differently like monotrichous, lophotrichous, amphitrichous and peritrichous. According to the arrangement they are classified into different classes and those bacteria are motile.