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Body Movements

Human Body and its movements, Ball and socket joints, Gait of Animals, Pivotal Joint, Hinge joints, Fixed joints etc.

Body Movements

Animals follow different ways to move from one place to another such as walking, running, flying, jumping, creeping, crawling, slithering, and swimming. The human skeleton is the internal framework that facilitates body movements. Thus, the human body is capable of performing a variety of movements.

Human Body and its Movements:

  • Rotates completely (Arm at the shoulder), rotates partly / turns (Neck), bends (Arm at Elbow), Lifts (Heel), no movement (Upper Jaw)
  • Bones in our body cannot be bent. We can bend or move our body only at those points where bones meet known as Joints

Various activities and movements are carried out by our body with the help of the joints named below:

  • Socket and ball joints: Socket and ball joints allow movements in every direction
  • Pivotal Joint: The joint at which the neck gets joined to the head is a pivotal joint. It helps us to bend our head backward and forward and turn the head right or left
  • Hinge joints: These joints allow back and forth movement like a door. The hinge joint at elbows allows only a back-and-forth movement
  • Fixed joints: Bones cannot move at fixed joints. E.g. Bones in our head, the joint between the rest of the head and the upper jaw, etc

All the bones in our body form a framework, which is known as the Skeleton. It gives shape to the body. The human skeleton comprises the skull, the backbone, ribs and the breastbone, shoulder and hip bones, and the bones of hands and legs.

  • Ribs (bones of the chest) join the backbone and the chest bone together to form a box. This is called the Rib cage
  • The rib cage is joined to a series of bones stretching from the neck to the pelvis known as the Backbone (Spine). The backbone has 33 vertebrae (individual, interlocking bones)
  • Pelvic bones (Pelvis) enclose the portion below the stomach. This is the part we sit on
  • The skull is made by many bones joining together. It protects and encloses the brain

The additional parts of the skeleton that can bend and are not as hard as the bones are called cartilage. For example, ear lobes, nose tip, etc. Cartilage is also found in the joints of the body and acts as rubber-like padding

  • Muscles are soft tissues that can contract to produce movement and strength. The muscles become short, stiff, and thick, when contracted. Muscles can only be pulled. Therefore, to move the bones, the two muscles need to work in pairs

The Gait of Animals:

  • Earthworms:
  • An earthworm doesn’t have any bones. Its muscles help it in movement by alternate extension and contraction of the earthworm’s body
  • Earthworms are known as farmers’ best friends since they eat their way through the soil and make the soil more useful for plants
  • Snail:
  • Move with the help of a muscular foot
  • Shell (outer skeleton) plays no role in the movement
  • Cockroach:
  • They have the muscles of the breast connected with the three pairs of legs and the two pairs of wings that help the cockroach to walk and fly
  • Birds:
  • Strong muscles and hollow, light bones together help the birds fly
  • They fly by fluttering their wings
  • Fish:
  • Fish form loops alternately on two sides of their bodies to swim
  • Streamlined body shape enables water to flow around it easily and helps the fish to move in the water
  • Snakes:
  • By looping sideways, snakes slither on the ground
  • The body is pushed forward by many bones and associated muscles

Conclusion

Body movements are of various kinds, such as walking, jumping, crawling, and swimming. These are made possible through the help of joints and bones. Various kinds of joints exist, such as ball and socket joint which moves in every direction, pivotal joint which joins the neck to the head, and fixed joints that do not allow the movement of bones. Bones, too, are of many kinds. These include the rib cage, the spine, the pelvis and the skull. Each of these bones serve a specific purpose. Animals have a different gait, which is the manner in which an animal or individual walks, which occurs due to the difference in body structures.