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 depend on 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. 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.