We are surrounded by living and
non-living things. All animals and plants are living things and biology is the
study of these living things. A cat playing with a ball is obviously living. A
pigeon flying from tree to tree is also a living thing.
Sometimes it is not so easy to
decide. Plants are living things but they do not play with balls or fly. If
something is living it will carry out all of the seven activities shown
opposite.
Some non-living things show one or
two of the seven characteristics of living things. Machines, such as washing
machines, can move. The car needs to be fed with petrol in order to move.
Crystals, such as ice crystals
forming on a window, grow bigger if the conditions are right. For something to
be living it has to show all of the seven characteristics of
living things.
Sand, wood and glass are all
non-living things. None of them shows any of the characteristics listed above.
Non-living things can be divided into two groups. First, come those which were
never part of a living thing, such as stone and gold.
The second group are those which
were once part of living things. Coal is a good example. It was formed when
trees died and sank into the soft ground. This happened many millions of years
ago when the Earth was covered with forests. Paper is non-living but it is also
made from trees. Jam is also non-living but it was made from the fruit of a
plant.
The Seven Characteristics of Living
Things
All living organisms need to take
substances from their environment to obtain energy, to grow and to stay
healthy.
All living organisms show movement
of one kind or another. All living organisms have internal movement, which
means that they have the ability of moving substances from one part of their
body to another. Some living organisms show external movement as well - they
can move from place to place by walking, flying or swimming.
All living things exchange gases
with their environment. Animals take in oxygen and breathe out carbon dioxide.
Excretion is the removal of waste
from the body. If this waste was allowed to remain in the body it could be
poisonous. Humans produce a liquid waste called urine. We also excrete waste
when we breathe out. All living things need to remove waste from their bodies.
When living things feed they gain
energy. Some of this energy is used in growth. Living things become larger and
more complicated as they grow.
Living things react to changes
around them. We react to touch, light, heat, cold and sound, as do other living
things.
All living things produce young.
Humans make babies, cats produce kittens and pigeons lay eggs. Plants also
reproduce. Many make seeds which can germinate and grow into new plants.
video Characteristics living and non living things
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