CONTENT

• What is locomotion and movement ?

• Why do animals need to do locomotion ?

• Movement in animals

• Organs of locomotion in microorganisms

• Organs of locomotion in invertebrates

• Organs of locomotion in vertebrates

• Organs of locomotion in sea animals

• Organs of locomotion in Aerial animals

• Movement in plants

• Movement humans

• Bibliography

• Locomotion means movement or the ability to move from one place to another.

• Movement is an act of moving.

This is locomotion

Why do animals need to do locomotion ?

• Animals need to do locomotion because they need to:

1. Search for food and; water and shelter

2. escape from danger example prey

3. Avoid unfavorable condition example migration

4. reproduce or to find a mate

Movement in animals

• All animals move at some time in their lives. Even those animals which are fixed or stationary begin life as free-swimming organisms. In certain organisms, the life-cycle consists of a sedentary (polyp ) generation alternating with a swimming ( medusa ) generation. For example. The jelly fish spends most of its life as medusa, while corals and sea anemones spend most of their lives as polyps.

• Most animal run, crawl, swim, fly with aid of limbs. The limbs are moved by muscles which are attached to the skeleton. When the muscles contract they move the skeleton, and with it part or all of the body.

• Not all animals need limbs to move quickly:

1) Snake are limbless. A snake moves by forming its body into zig - zag, gripping the ground with its undersides and pushing itself forward. The fastest snake, the black mamba, can reach over 30km/h.

2) animals such as flatworms often move by undulating in a continuous ripple.

Movement in animals

This picture shows that how a bird fly’s with the help of its wings

Organs of locomotion in microorganisms

• Flagella : a flagellum is a whiplike appendage that sticks out of the body. The flagellum moves the organism through the water, somewhat like the proppeler of an airplane pulls it through the air. Hence we can say that the flagellum acts like a little motor.

the flagellum is located on the anterior ( front ) end, and twirls in such a way as to pull the cell through the water. Example : euglena and chlamydomanas

• Cilia : the outer surface of the cell of certain organisms like the paramoecium is covered with many hundreds of tiny hair-like structure scalled cilia. These act like microscopic oars to push through the water enabling the organism to swim. In paramoecium the speed of motion is about four times its own length per second. As it moves through the water it rotate on its axis and small particles of debris and food are collected and swept into the gullet.

• Pseudopodia: Formation of Pseudopodia ( false legs ) in any direction leads to movement of the animal in that direction. Movement due to Pseudopodia is known as amoeboid movement. Example –amoeba.

Organisms of locomotion in invertebrates

• The organs of locomotion in the lower animals are varied wings, tube feet, muscular feet and walking legs are some of the locomotry organs found in these animals.

• Some invertebrates like roundworms, flatworms, squids, octopus, jellyfish, etc., lack special organs of locomotion. Such land animals are propelled by the muscular contractions while aquatic animals swim by pumping water in and out of their body.

Organisms of locomotion in vertebrates

• There are five classes of vertebrates :

1. Pisces ( fish )

2. Amphibians ( frogs, toads, salamander )

3. Reptiles ( snakes, turtles, crocodiles, lizards )

4. Aves ( birds )

5. Mammals ( humans, whales, dolphins, bats, horses, rats, pigs, bears, seals, walruses, etc. )

• Of these members of the class Pisces are exclusively aquatic. Amphibians, certain reptiles, birds, and mammals are able to move on the land as well in water.

Organisms of locomotion in sea animals

Fins, flippers and webbed feet

• Movement in water is facilitated by means of flippers in whales, seals and sea lions, fins in fishes and webbed feet in ducks and frogs.

• Fins are modified limbs arising as flat appendages on the body of the fish. most fish swim with side to side strokes of their tale fin, accompanied by a wriggling movement of the body. They use their fins for steering ( changing direction) and balance.

• Dolphins , porpoises, manatees and whales are mammals that live their entire life in water. They have a streamlined body and a powerful tail, which they move up and down to propel themselves through the water. Their forelimbs are paddle-like flippers, used for balance and steering. They have no hindlimbs.

• Some animals like hippopotamuses and walruses spend much, but not all, of their time in water. They swim by moving their forelimbs and their hindlimbs.

A hippopotamus

This picture shows how a hippopotamus moves by using its forelimbs and hindlimbs both

Organisms of locomotion in Aerial animals

Wings

• Wings are expanded appendages speialised for flight.

• In birds, the forelimbs are modified into wings.

• Birds flap their wingd in order to fly. A bird gets most of its lift by flapping its wings. This motion pushes air downwards, producing an upward reaction force or upthrust. Also, when the wings are apread, the volume is increased. Thus, the upthrust also increase.

Bird flying

This picture shows how the bird is pushing the air down and making its movement up to fly.

Movement in plants

• Plants can move too. They move when they grow towards the light, also their stems grow upwards and their roots grow down.

• Protoplasm is sensitive to various external agencies such as heat, light, electricity, gravity, certain chemicals, etc., which act as stimuli and plants or plant organs often respond to such stimuli by movement of their body in a particular direction.

Movement in plants

Movement in humans

• The framework of the human body the skeleton, the muscles and the skin is a strong yet flexible construct. The 206 bones that make up the adult skeleton support the body and work with muscles and nerves to move the body's various parts.

• The human body has about 650 muscles responsible for movement and even the smallest motion requires at least 2 muscles working in opposition.

• All movements that change the positions of the bony parts of the body, occur at joints. The skeletal system consists of many separate bones, most of which are held together at joints by flexible connective tissue. Joints are necessary since bones are too rigid to bend without causing damage.

Movement in humans

This picture shows how a man is moving is feet to run

A skeleton

Joints

• Joints are the place where two bones meet. All of your bones, except for one (the hyoid bone in your neck), form a joint with another bone. Joints hold your bones together and allow your rigid skeleton to move.

• Some of your joints, like those in your skull, are fixed and don't allow any movement. The bones in your skull are held together with fibrous connective tissue

• Other joints, such as those between the vertebrae in your spine, which are connected to each other by pads of cartilage, can only move a small amount.

Body joints

These are all the joints which are available in our body like elbows and knees

Bibliography

• A textbook of biology by Anita Prasad for class VII

• www.google.com/imghp

• http://www.bbc.co.uk/science/humanbody/body/factfiles/joints/ball_and_socket_joint.shtml

• www.google.com