Characteristics Of Organisms

We have so many things around us, but how many of them are living? If plants are living entities, why don’t they move? If all living things move, are buses and cars living things too? The answer to all these questions is that living things exhibit certain features. These features help us decide if they are living or non-living. Following are the characteristics based on which a student can easily conclude if an entity is living or not.

Do All Organisms Need Food?

All living things need food to survive. Plants produce their own food. Human beings and animals depend on plants for their food. It gives them the energy to perform their daily activities and energy to carry out life processes inside the body.

Do All Organisms Show Growth?

We grow with time. Every living thing grows. It may not be a visible change, but with time we show changes. For example, we are taller than what we used to be in our childhood, kittens turn into cats, a chick hatches from an egg to grow into a hen or cock. etc. Plants grow into different sizes and shapes with time, right from germination up till a mature tree.

Do All Organisms Respire?

We cannot live without breathing air. Animals and human beings inhale oxygen produced by plants and exhale carbon dioxide, this process is called respiration. It is through this process that energy is finally obtained from the food we take. Some animals, however, have different breathing mechanisms, for example, earthworms breathe through their skin, fish absorb the oxygen dissolved in the water through gills.

Respiration in plants is brought about by leaves through small pores on them. In the presence of sunlight, they take in carbon dioxide and give out oxygen through the process of photosynthesis. Amount of oxygen released in the process of food preparation by plants is much more than the oxygen used in respiration.

Do All Organisms Respond To Stimuli?

We all respond to the changes that take place in our environment. For instance, we might quickly pull our hands away if we touch a very hot surface. This response to the changes is called as stimuli. For example, an octopus releases a noxious cloud of ink if it is attacked by a predator. Cockroaches begin to move when we suddenly turn on lights since they are light-sensitive. Even plants respond to stimuli too, for instance, the Mimosa plant or the ‘touch-me-not’ plant folds its leaves upon being touched.

Living Organisms And Excretion

We all need food to survive. And not all food can be fully digested by our body. Elimination of this undigested waste from our body is called excretion. Plants use a different mechanism for excretion, some secrete, while others store up these wastes in a way that they do not harm other parts of the plant.

Do All Organisms Reproduce?

All organisms reproduce and it is one of the most basic requirements to ensure the survival of their species. There are different modes of reproduction. Some lay eggs, others give birth to younger ones. Plants reproduce through pollination, budding, fragmentation, spore formation and so on.

Do All Organisms Move?

All living organisms exhibit some form of movement. It is necessary for fulfilling the various functions required for survival (such as acquiring food, escaping predation, finding mates etc). Even plants exhibit some movement, though they are anchored in the soil.