Two-kingdom classification, Biology

Assignment Help:

Two-Kingdom Classification

The history of taxonomy is as old as man himself. It may be traced back to prehistoric times because man had learnt to designate living organisms by specific names very early in his evolutionary history. Much before the advent of civilisation living things had been categorised into animals and plants. Hippocrates (460-370 BC), Aristotle (384-322 BC) and many others had tried to put some order into the chaos of the bewilderingly large number of different life forms. Aristotle appears to have been the first to attempt a logical system of classification. He classified animals on the basis of presence or absence of blood as Sanguineous (with blood) and Non-sanguineous (without blood). He believed that in evolution, life had been directed towards a perfect animal form, having blood (Table 1.6). He incorporated this idea which is a hierarchical system of classification In his book entitled 'Scala Naturae'. He also recognised two kingdoms in the living world i.e., Plantae and Animalia. The former included mainly immobile forms, while the latter embraced mobile forms. We also know that one of the major differences between the two is that the members of Kingdom Plantae are autotrophic and obtain their food mostly by photosynthetic means and those of Kingdom Animalia are heterotrophic and obtain their food by ingestion.

Table: Aristotle's 'Scale of life' or Scala Naturae.

1839_Two-Kingdom Classification.png


Kingdom Plantae was later divided by biologists into two subkingdoms,

  1. Thallophyta containing the phylum Algae (with chlorophyll) and Phylum Fungi (without chlorophyll) and
  2. Embryophyta with phylum Bryophyta (liverworts and mosses) and Phylum Tracheophyta (vascular plants).

Kingdom Animalia, on the other hand, was divided into Subkingdoms Protozoa containing unicellular forms and Sub Kingdom Metazoa including sponges and other multicellular organisms. A third Sub Kingdom Parazoa was later created and the sponges were shifted to this Sub Kingdom due to their intermediate position. between uni and multicellular organisms.


Related Discussions:- Two-kingdom classification

How to use atp to make reactions go, What do enzymes do, and how? How is en...

What do enzymes do, and how? How is enzyme activity regulated in cells? How do ATPases u se ATP to make reactions go?

Define the historical example of neuroscience, Normal 0 false ...

Normal 0 false false false EN-IN X-NONE X-NONE

Explain the frank furcal perforation, Explain the Frank Furcal Perforation ...

Explain the Frank Furcal Perforation a) Coronal perforation at the pulpal floor of multirooted tooth. b) Due to excessive deepening at the pulpal floor during access perfora

Describe in brief about retina, Describe in brief about retina The reti...

Describe in brief about retina The retina is a highly complex layer of nervous tissue. The photoreceptors are rods and cones for scotopic and photopic vision respectively. The

What is a membrane, What is a membrane? Membrane is any delicate sheet ...

What is a membrane? Membrane is any delicate sheet that divides one region from another blocking or permitting (selectively or completely) the passage of substances. The skin,

Release of microspores, Release of Microspores Up to the tetrad stage...

Release of Microspores Up to the tetrad stage, there is no cellulosic wall around the microspores. As you will come to know in the next unit, a unique feature of the pollen i

How can the formation of egg cells from germ cells, Indicating the name and...

Indicating the name and respective ploidy of each involved cell how can the formation of egg cells from germ cells be described? The formation of egg cells starts with a germ c

Difference between unconditioned & conditioned reflex action, Difference be...

Difference between unconditioned and conditioned reflex action- S.NO .   1. UNCONDITIONED   It is inborn CONDITIONED

Hutchinson phyletic dieta, hi there,i would like u to help me with understa...

hi there,i would like u to help me with understanding Hutchinson phyletic dieta

Embryonic induction and cell determination, Embryonic Induction and Cell De...

Embryonic Induction and Cell Determination The cell determination or fate of embryonic cells is regulated through factors which may reside within the embryonic cells or by the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd