Three and four kingdom classification, Biology

Assignment Help:

Three and Four Kingdom Classification

The two-kingdom classification, while solving many of the problems of classification, failed to establish clear-cut distinction between plants and animals. It also could not indicate correct relationships among organisms. Difficulty was particularly felt at the unicellular level. There are forms like Euglena and Volvox which possess both plant and animal like characters. On the one had like plants they contain chlorophyll and manufacture their food by photosynthesis.

On the other Kind the" actively swim like animals. Due to this reason zoologists classified them with animals under phylum protozoa while botanists included them as plants under Thallophyta. In addition to this, there are some other organisms like Peranema which closely resemble Euglena in structure but lack chlorophyll. These are not included among plants but were always classified under Protozoa. In order to overcome such difficulties, Haeckel (1866) proposed setting up of a third kingdom under the name Protista (meaning the very first) to include all thallophytes and protozoans. This kingdom also included bacteria and blue-green algae. According to this system the old kingdom Plantae included only the members of Embryophyta while Animalia was left only with Parazoa and Metazoa. However, many forms such as blue-green algae and bacteria of Protista lack membrane- bound nuclei. So, a fourth kingdom, Monera, was later established by Whittaker in order to accommodate these forms. From the evolutionary point of view the kingdom Monera is regarded as the most primitive.


Related Discussions:- Three and four kingdom classification

Standard titration - estimation of vitamin c in chillies, Define Standard t...

Define Standard titration - estimation of vitamin c in Chillies? Pipette 5 ml of standard ascorbic acid solution into a 100 ml conical flask. Fill the burette with the dye solu

Explain the mechanisms of heat loss, Name and explain the mechanisms of hea...

Name and explain the mechanisms of heat loss that are contributing to Joel's feelings of coldness. Be sure to name ALL the mechanisms that are contributing!

What is alara, Question 1 Discuss the biological factors influencing ra...

Question 1 Discuss the biological factors influencing radioactivity Question 2 Explain the quality assurance of computed Tomography Question 3 Write short

Financial accounting software, Financial Accounting Software An Ide...

Financial Accounting Software An Ideal Accounting Software should have the following features:  Purchase Details  Invoice Details  Purchase/Sale Return (Debit/Cre

Role of nucleic acids in metabolism, ROL E OF NUCLEIC ACIDS - These...

ROL E OF NUCLEIC ACIDS - These are DNA / RNA. Unit is nucleotides. Present in viruses and all cells. DNA is concerned as genetic material. RNA as genetic material

Splenic abscess, Splenic infarction is a common complication of left-sided ...

Splenic infarction is a common complication of left-sided IE (40 per cent of cases). Only 5 per cent of patients with splenic infarction will develop splenic abscess. This infectio

Dietary fibre requirement during diabetes, Q. Dietary Fibre requirement dur...

Q. Dietary Fibre requirement during diabetes? Dietary fibre is that part of food which is not digested by the intestines. High fibre meals have shown to give the best glycemic

Lactation, LACTATION - Production of milk in the female's breasts af...

LACTATION - Production of milk in the female's breasts after delivery is lactation. Prolactin is responsible to synthesize milk in breast. Oxytocin is responsibleto gi

Describe the functional problems of implant failures, Functional Problems o...

Functional Problems of implant failures The masticatory efficiency of the implant supported prosthesis depends on the anchorage related factors and the prosthesis related fact

Preparation of the laboratory samples, Q. Preparation of the Laboratory Sam...

Q. Preparation of the Laboratory Samples From the primary sample while selecting a representative laboratory sample, we need to consider the following: a) Laboratory sampl

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