My Science School

               One of the ways nature contributes to Man’s well-being is by providing him with its manifold produce. Honey is an invaluable substance that Man receives from nature. It is used not only as a sweetening agent, but also for its medicinal properties.

               Honey, as we all know, is produced by the honeybee, a widely distributed flying insect known for its ability to collect nectar from flowers. Bees have stocky bodies that are covered with hair to which pollen adheres. The honeybee is considered as an important pollinator of crops.

               Honeybees are social insects that live in large colonies. The queen bee, drones and worker bees all have specific tasks to help support the colony. The queen bee lays hundreds of eggs. It is the duty of the worker bees to bring food to the colony. When worker bees locate a new source of food, they move in circles, wagging their bodies to show other bees the location of this source. In fact, they look as though they are dancing, and this action of the bees is called the ‘bee dance’.

Picture credit: google

 

               From time immemorial, the question of how this Universe came to be has haunted Man’s mind. While ancient Man chose to believe in the easiest answer that everything came into existence-through an act of God, modern science persisted with rational enquiries that proved otherwise. Have you ever wondered what it must have been like millions and millions of years ago, when the earth first came into existence? Were there plants and animals then?

               When the earth was first formed, there was no life on it. Its surface was extremely hot and had giant volcanoes that threw fiery rocks, dust, and gases into the air. Scientists estimate that the first life forms on Earth were primitive, single-celled organisms. They must have appeared about three billion years ago in the oceans. They had no bones or shells, so they looked more like worms and jellyfish. These one-celled organisms gradually became multi-cellular organisms. As time passed, more complex forms of life began to fill up oceans. One of the first forms of life was a very simple plant called algae. Different types of plants came later on. And so, yes, animal life appeared only after the appearance of plant life.

            You must have observed huge trees in your own backyard that have been staying in the same place for years, without any explicit signs of movement. Unlike animals, trees cannot move about, eat through the mouth, express emotions and communicate their needs. Plants and animals are as different from each other as a rose is from a rabbit!

            Generally, plants, with a few exceptions like the swimming algae, cannot move about from place to place, while animals can move freely. One of the most distinguishing features of plants is that they can make their own food with the help of their green colouring, which is called chlorophyll. On the other hand, animals must rely on plants for their food, or hunt other animals. Animals have a nervous system, which makes them sensitive to touch, heat, cold, pain, and other stimuli. Plants lack such a nervous system. However, as you must have observed, some plants such as the touch-me-not, do fold their leaves when touched. Others sense that a support is near, and twine themselves around it.

            The cell structure of plants and animals is different too. Most plants have rigid cell walls and contain cellulose. Animal cells do not have cellulose. The development of animals and plants is different too. While animals stop growing when they reach maturity, plants do not stop growing until they die!

 

 

 

 

 

 

 

 

 

 

 

              Have you observed the carcass of an animal or a bird decomposing and disintegrating into the soil? If you observe closely, you could find small maggots or worms that eat up the dead body. When animals or plants die, they slowly become part of the soil thanks to the presence of decomposers.

             Decomposers play a crucial role in the process of recycling. They eat away the dead remains of the plants and the animals. They have the capability of breaking down organic matter and converting them into simpler substances. This means that these substances go through a cyclical life by being integrated into organisms and are used repeatedly.

              Nowadays, people are encouraged to use biodegradable materials. Materials that can be broken down into simpler substances naturally are called biodegradable materials. However, human activities have hindered the process of natural recycling.

              Materials such as tin, plastic and glass are non-biodegradable. These materials cannot be broken down naturally; and therefore, they can remain in the environment for hundreds or thousands of years. They can pose a threat to life and are possible health hazards.

             Governments, these days, are urging people to replace non-biodegradable products with biodegradable products.

            If every living thing is comfortably placed in nature and allowed to grow and multiply at leisure, the earth would soon become inadequate for life! Therefore, the equilibrium of life on earth should be kept in check. Food chains play that vital role in our environment.

            Every living thing, at one or other time, is consumed by another. The process of who eats whom is called food chain. It is basically, a series of living beings linked together because each one is the food for another. The position each species occupies within a food chain is called a feeding level. Thus, plants come to the first as they represent the lowest level. The final consumer comes at the last level. Thus a pyramid is formed in the biosphere.

            For example, grasshoppers eat plants; meanwhile, grasshoppers become prey to frogs. Snakes consume frogs. However, snakes are eaten by peacocks, which is the final consumer in the pyramid. When the final consumer at the top of the pyramid dies and disintegrates, its substances are taken up as nourishment by plants. Thus this chain or cycle continues. If any of the links is lost or damaged it affects the whole chain. All living beings are inter-connected and inter-dependent; and therefore, all living things are part of this chain.