All living organisms are classified into five kingdoms:
In this section, let discuss in brief about kingdom Animalia, Plantae, and Viruses.
Also Read: Kingdom Monera, Protista, Fungi
- Kingdom Animalia includes all the multicellular, eukaryotic, heterotrophic organisms.
- These animals cannot prepare their own food and hence belong to other organisms for nourishment.
- The organisms belonging to kingdom Animalia lack cell walls.
- About 800,000 different species and 36 separate phyla have been identified under kingdom Animalia.
- They exhibit all the levels of organization in structure i.e. they range from primitive organization to the organ system level of organization
- They reproduce sexually as well as asexually.
- They also have the ability to regrow the missing parts. This process is known as regeneration.
- Few animals ingest their food and digest it in an internal cavity.
- Most animals possess the ability to move from one place to another in search of one place to the other. These are known as motile animals. The animals that cannot move are known as sessile.
- Kingdom Plantae includes all the eukaryotic, multicellular plants, that perform photosynthesis to prepare their food.
- Plants have rigid cell walls made of cellulose and pectin.
- They possess organelles like chloroplast and chlorophyll that facilitate photosynthesis.
- These are non-motile.
- They can reproduce sexually as well as asexually.
- Few plants such as pitcher plant cannot prepare their own food and feed on insects to derive nutrition.
- They are beneficial to maintain ecological balance. A reduction in the number of plants has resulted in global warming.
- The members of kingdom Plantae have a unique life cycle which follows alternation of generation between two phases – diploid sporophytic phase and haploid gametophytic phase.
- Viruses are microscopic organisms that are known to be the connecting link between living and non-living.
- These were not placed under the five-kingdom classification since they are neither living nor dead. hence they form their own group.
- Viruses are devoid of cells and cell organelles. Therefore, they depend upon the machinery of the host cell to replicate and synthesize proteins.
- Viruses are usually smaller than bacteria in size. The first virus to be discovered was the Tobacco mosaic virus (TMV) that infects the tobacco plant.
- Viruses basically consist of genetic material i.e. nucleic acid (DNA or RNA) surrounded by a protein capsule.
Also Read: Five Kingdom Classification
For more information on kingdom Plantae, Animalia and viruses, keep visiting BYJU’S website or download BYJU’S app for further reference.