NCERT Book Class 11 Biology Chapter 17 Locomotion and Movement

LOCOMOTION AND MOVEMENT 217

C HAPTER 17
LOCOMOTION AND MOVEMENT
17.1 Types of Movement is one of the significant features of living beings. Animals and
Movement plants exhibit a wide range of movements. Streaming of protoplasm in
the unicellular organisms like Amoeba is a simple form of movement.
17.2 Muscle
Movement of cilia, flagella and tentacles are shown by many organisms.
17.3 Skeletal Human beings can move limbs, jaws, eyelids, tongue, etc. Some of the
System movements result in a change of place or location. Such voluntary
17.4 Joints movements are called locomotion. Walking, running, climbing, flying,
swimming are all some forms of locomotory movements. Locomotory
17.5 Disorders of
structures need not be different from those affecting other types of
Muscular and
movements. For example, in Paramoecium, cilia helps in the movement of
Skeletal System
food through cytopharynx and in locomotion as well. Hydra can use its
tentacles for capturing its prey and also use them for locomotion. We use
limbs for changes in body postures and locomotion as well. The above
observations suggest that movements and locomotion cannot be studied
separately. The two may be linked by stating that all locomotions are
movements but all movements are not locomotions.
Methods of locomotion performed by animals vary with their habitats
and the demand of the situation. However, locomotion is generally for
search of food, shelter, mate, suitable breeding grounds, favourable
climatic conditions or to escape from enemies/predators.

17.1 TYPES OF MOVEMENT
Cells of the human body exhibit three main types of movements, namely,
amoeboid, ciliary and muscular.