Having an ordered structure, requiring energy, responding to stimuli and adjusting to environmental changes, and being capable of reproduction, growth, movement, metabolism, and death are the basic features. Living organisms are currently divided into three domains: (Eu)Bacteria (real bacteria), Archaea (archaebacteria), and Eukarya (archaebacteria).

The term “living” comes from the Old English lifende, which means “to live” or “to be alive.” The word thing is derived from the Old English word ing, which means “entity,” “being,” “body,” or “stuff.” Organism, life form, and creature are all synonyms.

The ability to carry out life processes such as movement, respiration, growth, reactivity to environmental stimuli, and reproduction distinguishes living entities from non-living objects. This way of life may be appropriate for this age group, but it has some drawbacks and can lead to the alternative ideas listed above. Students, for example, may not notice plant movement and, as a result, may not perceive plants to be alive.

Characteristics of Living Things

Defining a living entity, as well as “life”—the property held by living things—is a challenging task. A living entity, on the other hand, has specific characteristics that help define what life is.

Complex organization

Living things have a level of intricacy and order that non-living things lack. A living organism is made up of one or more cells at its most basic level. Tissues are made up of these units, which are usually too small to view with the naked eye. A tissue is a collection of cells that perform a common purpose. Organs like the stomach and kidney are made up of tissues. An organ system is made up of several organs that act together. An organism is made up of a complicated system of organs.

Metabolism

Metabolism is the fast turnover of chemical compounds that occurs in living things. Metabolism entails chemical interactions with the outside world as well as substantial organic matter transformations within a live organism’s cells. Metabolism is the process of releasing or using chemical energy. Metabolic activity is not visible in non living substances.

Responsiveness

An organism’s responses to changes in the environment must be coordinated in order to respond effectively. An organism’s functions are coordinated by a system of neurons and a number of chemical regulators known as hormones. A variety of effectors, such as muscles and glands, help the organism respond to stimuli. In most cases, energy is used in the process.

All living creatures have the ability to respond to stimuli in their surroundings. Living organisms, for example, respond to changes in light, heat, sound, as well as chemical and mechanical contact. Organisms contain sensory organs such as eyes, hearing, and taste buds that let them detect stimuli.

Growth

A living entity changes materials that are unlike itself into materials that are similar to itself as it grows. When a person digests a meal of meat and vegetables, for example, the chemical material is transformed into more of himself or herself. This is not a property of a non living entity.

Reproduction

Reproduction is the process through which a living entity can make duplicates of itself. While the organism is still alive, copies are made. Reproduction is frequently an extension of the growth process in plants and simple animals. Sexual reproduction is a type of reproduction in which two parents contribute to the development of a new individual in more complex organisms. A new combination of qualities can be created during this procedure.

Only one parent is involved in asexual reproduction, and the offspring are nearly identical to the parent cell. Bacteria, for example, develop swiftly to maturity before splitting into two entities via binary fission, an asexual reproductive mechanism.

Death

Things that are alive will pass away. A living creature has a life, it’s existence will come to an end at some point. Biological ageing is referred to as senescence. It occurs when the health of living things deteriorates over time. The organism’s ability to function deteriorates over time. As a result, it is more susceptible to illnesses and malfunction. Some living organisms are thought to be eternal because they appear to be immune to death.

Non-cellular life

Viruses are sometimes mistaken for living organisms because they appear to be alive when they are within their hosts. They have genetic material, reproduce, and evolve through natural selection. Others, on the other hand, do not regard them as living creatures because they are essentially dead when they are not in their host. Viruses are unable to multiply on their own.

Evolution

Through evolution, living species have the ability to adapt to their surroundings. Populations evolve over time, and the organisms inside them improve their ability to metabolise, respond, and reproduce. They acquire the ability to cope with their surroundings that their forefathers lacked.

Ecology

The environment has an impact on the living creatures in its vicinity. Ecology is the study of how organisms interact with one another and in their surroundings. The environment can be influenced by both biotic (living things) and abiotic (nonliving) elements. Rain and sunlight, for example, are non-living elements that have a significant impact on the ecosystem. If the environment gets too challenging to exist in, living beings may migrate or hibernate.

Classification of Living Things

Initially, living things were classed as either plants or animals. Animals and plants are both eukaryotes, however they are characterised by their distinguishing properties, such as motility, manner of nourishment, and cellular structures. Animals are non-motile and have a cell wall, whereas plants are photosynthetic, and do not have a cell wall. Bacteria and archaea, on the other hand, are not plants or animals because they are prokaryotes (i.e. lacking in cytoplasmic organelles, including nucleus).

Domain » Kingdom » Phylum » Class » Order » Family » Genus » Species

All eukaryotic living entities are included in the domain Eukarya. Animals, plants, fungus, algae, and protists are in them. Within their cells, they have membrane-bound organelles.

One of the differences between bacteria and archaea is that of RNA polymerase. It has ten sub-units in archaea. It contains four bacteria. The composition of the cell wall is an example. The peptidoglycan in archaeal cell walls is absent, but peptidoglycan is present in bacterial cell walls.

Properties of the Five Kingdoms:

The five kingdoms have the following characteristics:

Monera

The type of cell is prokaryotic. The cell wall is non-cellulosic and present. The nuclear membrane has been removed. It is a single-celled organism that feeds both autotrophically and heterotrophically. Bacteria are an example of a monera kingdom organism.

Protista

The type of cell is eukaryotic. There is a cell wall present. There is also a nuclear membrane present. It is a single-celled creature with an autotrophic mode of nourishment.

Fungi

The type of cell is eukaryotic. There is a cell wall present. The nuclear membrane is also present, and the organism is multicellular with a heterotrophic nutrition mode. A fungus, for example, is a mushroom. They are unable to prepare their own meals.

Plantae

The type of cell is eukaryotic. The cell wall is not made of cellulosic material. The nucleoplasmic membrane is visible. Tissue or organ is the organism. Autotrophic nutrition is the mode of nourishment. Plants, trees, and a bush are examples.

Animalia

The type of cell is eukaryotic. The cell wall has been removed. The nucleoplasmic membrane is visible. A tissue, organ, or organ system is the organism. Heterotrophic nutrition is the mode of nutrition.

Conclusion

Any organism or life form that possesses or exhibits the properties of life or being alive is referred to as a living thing. Having an ordered structure, requiring energy, responding to stimuli and adjusting to environmental changes, and being capable of reproduction, growth, movement, metabolism, and death are the basic features. Living organisms are currently divided into three domains: (Eu)Bacteria (real bacteria), Archaea (archaebacteria), and Eucarya (archaebacteria).