Page 116 - Science Class 06

transporta on like cars, aircra , etc. Move- understanding the difference between
ment, on the other hand, refers to any type of
mo on. Movement can be both voluntary and
involuntary. For example, hammering a nail is
a voluntary movement, while breathing is an
involuntary movement.
Let us be er understand these concepts by
Locomo on
1. Moving away from the original
posi on of an organism is locomo on.
2. It is always voluntary.
3. Locomo on takes place at the
organism level.
4. Locomo on doesn’t necessarily
require energy when a free-floa ng
organism is considered.
MOVEMENT IN HUMAN BEINGS
Locomo on and movement takes place in
human beings by contrac on of skeletal
muscle. At least two muscles are needed to
move a joint. On the opposite side of the
joint, there is an extensor muscle. This
straightens the joint. Since flexor and
extensor muscles pull a joint to opposite
direc ons, our body parts become able to
move.
The bones moved by contrac on and
relaxa on of two sets of muscles are biceps
and triceps, both muscles work together.
When one set contracts, the bones are
pulled in that direc on and vise-versa.
Flexor Muscles
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locomo on and movement from the table
given below:
While both locomo on and movement
sound similar in their meaning, there are a
few interes ng differences between these
two.
Movement
1. Movement can happen with or
without moving away from an
organism’s original posi on.
2. It can either be voluntary or
involuntary.
3. A movement takes place at the
biological level.
4. Movement requires energy.
Extensor Muscles
Tendons
Muscles are a ached to bones by tough and
inelas c fibres called tendons.
The tendons concentrate the pull of the
muscle into a small area.
The pelvic girdles are connected with each
other and to the sacrum. In the way, a very
long structure is formed through which
backward thrust is given by the hind legs
against the ground and we move forward.
Science-6