expain exchange of gases in living and non living components
Answers
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 below.
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.
Non-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.