Biological Classification MCQ Quiz - Objective Question with Answer for Biological Classification - Download Free PDF

The correct answer is C, E, A, D, B

Concept:

• R.H. Whittaker proposed the five-kingdom classification system in 1969.
• This system classifies all living organisms into five kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.

Characteristics of 5 Kingdom classification:-

Explanation:

• Prokaryotes with cell wall made of polysaccharides and amino acids (C): This represents Kingdom Monera, which consists of prokaryotic organisms like bacteria. They have the simplest organization without any true nucleus or membrane-bound organelles.
• Eukaryotes with cellular body organization (E): This represents Kingdom Protista, which includes unicellular eukaryotes like amoeba and paramecium. They have a more complex cellular structure compared to Monera, but lack specialized tissue organization.
• Multicellular heterotrophs with cell wall made of chitin (A): This represents Kingdom Fungi. Fungi include mainly multicellular organisms (like molds and mushrooms) with more complex structures than Protista, characterized by having a cell wall made of chitin.
• Eukaryotic autotrophs with tissue/organ level of body organization (D): This represents Kingdom Plantae, which includes multicellular plants. These organisms have specialized tissues and organs such as roots, stems, and leaves, leading to higher complexity.
• Heterotrophs with tissue/organ/organ system level of body organization (B): This represents Kingdom Animalia. Animals have the highest level of body organization with specialized organs and organ systems, making them the most complex in the hierarchy.

Therefore, the arrangement of the given characteristics in increasing order of complexity of body organization is: C, E, A, D, B.

The correct answer is 7

Explanation:

1. Viroids: These are infectious agents composed only of a short strand of circular RNA. They do not contain DNA.
2. Prions: These are infectious agents composed of protein only. They do not contain RNA or DNA.
3. TMV (Tobacco Mosaic Virus): This is a virus that contains RNA but not DNA.
4. Mycoplasma: These are bacteria that have both DNA and RNA.
5. Paramoecium: This is a genus of unicellular ciliates, a type of protist. They have both DNA and RNA.
6. Slime moulds: These are eukaryotic organisms that can live freely as single cells but can aggregate to form multicellular reproductive structures. They have both DNA and RNA.
7. Archaebacteria: These are microorganisms that have both DNA and RNA.
8. Rhizopus: This is a genus of common fungi. They have both DNA and RNA.
9. Yeast: This is a type of fungus (unicellular) that has both DNA and RNA.
10. Cuscuta: This is a genus of parasitic plants that have both DNA and RNA.

Therefore, the total members with both DNA and RNA are 7

The correct answer is Wilt disease

Explanation:

• Viruses are infectious agents that consist of genetic material (either DNA or RNA) surrounded by a protein coat called a capsid. In some cases, viruses may also have an outer lipid envelope.
• The protein coat called capsid made of small subunits called capsomeres, protects the nucleic acid.
• These capsomeres are arranged in helical or polyhedral geometric forms.
• Viruses cause diseases like mumps, small pox, herpes and influenza. AIDS in humans is also caused by a virus.
• In plants, the symptoms can be mosaic formation, leaf rolling and curling, yellowing and vein clearing, dwarfing and stunted growth.

The correct answer is A - RNA, B- Capsid

Explanation:

• Viruses contain genetic material, that could be either RNA or DNA.
• No virus contains both RNA and DNA.
• A virus is a nucleoprotein and the genetic material is infectious.
• Viruses that infect plants have single stranded RNA and viruses that infect animals have either single or double stranded RNA or double stranded DNA.
• The protein coat called capsid made of small subunits called capsomeres, protects the nucleic acid. 
• These capsomeres are arranged in helical or polyhedral geometric forms.

Fig: Tobacco mosaic virus

The correct answer is Double-stranded DNA

Explanation:

• Bacterial viruses or bacteriophages (viruses that infect the bacteria) are usually double-stranded DNA viruses.
• The protein coat called capsid made of small subunits called capsomeres, protects the nucleic acid.
• These capsomeres are arranged in helical or polyhedral geometric forms.

Fig: Bacteriophage

Concept:

• There are innumerable species of plants and animals and other organisms inhabiting the surface of the earth.
• To identify and study these species, it is necessary to develop a mechanism that has a universal application.
• Different life forms are identified and classified into different groups which helps in their study.

Explanation:

Different Systems of Classification - 

• Two Kingdom System of Classification:
  • Carl Linnaeus divided all the life forms present on the earth into two groups based on their mode of nutrition.
  • He gave the two Kingdom System which includes - Kingdom Plantae and Kingdom Animalia.
  • However, this system of classification was inadequate due to the vast majority of organisms found on earth.
• Five Kingdom System of Classification:
  • R.H. Whittaker proposed the Five Kingdom System of Classification.
  • According to R.H. Whittaker's Five Kingdom system, the living organisms are divided into the following Kingdoms - 

•    Kingdom Monera includes unicellular prokaryotic organisms. Eg: Pseudomonas
• Kingdom Protista includes unicellular eukaryotic organisms. Eg: Euglena
• Kingdom Plantae includes multicellular eukaryotic organisms. Includes autotrophs, semi-autotrophs, and insectivorous plants.
• Kingdom Fungi include multicellular eukaryotic organisms (except for yeast which is unicellular). These are mainly heterotrophs. E.g.- Saccharomyces cerevisiae
• Kingdom Animalia includes multicellular eukaryotes that are heterotrophs. These organisms have adapted to holozoic nutrition. E.g.- Human beings

So from the above-given information, the correct answer is option 1.   

The correct answer is the Virus.

Key Points

• The microbe that reproduces only inside the body of the host organism is Virus.
• The viruses are non-cellular organisms that are characterized by having an inert crystalline structure outside the living cell.
• They have a DNA or RNA core surrounded by a capsid, which is a protein covering.
• Influenza, colds, chicken pox, measles, polio, and AIDS are the diseases caused by viruses.
• Viruses cause diseases among animals and plants. Potato mosaic and tobacco mosaic are the common viral diseases among plants.

Additional Information 

Concept:

• Nutrition is a process by which an organism consumes and uses food materials. According to WHO, Nutrition is the intake of food, considered in relation to the body's dietary needs.
• The term, nutrition includes the processes like ingestion, digestion, absorption, assimilation & egestion. This is an important life process for obtaining energy for the body of that organism for carrying out all functions of cells and also to repair the cells.
• There are various modes of nutrition mainly, Autotrophic, Heterotrophic, Chemoautotrophic, Saprophytic,  etc.

Explanation:

• Fungi show the saprophytic mode of nutrition
• Saprophytic Nutrition:  In this type of nutrition the organism depends on the dead and decaying matter of other organisms for their food. 
• The fungi like Rhizopus, Penicillium, Mucor (pin mould), Yeast are the other examples of Saprophytes.
• Saprophytic fungi are also called natural cleaners because they degrade and decompose all the biological waste formed ( dead animals and plants) making our planet healthier, more beautiful, and a better place to live.

The image shows a saprophytic fungi bread mould growing on a slice of bread.

Additional Information

• Paramecium shows the holozoic mode of nutrition. Holozoic nutrition is a type of heterotrophic nutrition in which the food (solid, liquid, or gas) is directly ingested or engulfed into the body.
• Spirogyra shows the autotrophic mode of nutrition. In this type of nutrition, the organisms prepare their food by themselves.
• The bacteria Clostridium has several varieties that show different modes of nutrition. For Eg, Clostridium botulinum is a heterotroph while Clostridium perfringens is an anaerobic autotroph.

Concept:

• Living organisms are found throughout the world. They can be found on top of high mountains to deep seas.
• Living organisms are found in deserts, oceans, wetlands, grasslands, hot springs, etc.
• A living organism shows several characteristics such as growth, ability to reproduce, metabolism, ability to sense the environment and respond to it, and cellular organization.

Explanation:

• Option 1: Growth - INCORRECT
  • Growth can be defined as an increase in mass as well as an increase in the number of individuals.
  • All living organisms exhibit growth.
  • A multicellular organism shows growth by cell division.
  • In animals growth by cell division takes place up to certain age, whereas in plants this growth takes place throughout its life.
  • Thus growth is a characteristic of living organisms. 
  • However, it cannot be regarded as a defining property because non-living things like mountains and sand mounds also show growth.
  • The growth shown by these objects is through the accumulation of material on the surface.
• Option 2: Ability to make a sound - INCORRECT
  • Ability to make sound cannot be regarded as a defining property of living organisms.
  • This is because many lower living organisms do not have the ability to produce any sound.
• Option 3: Response to external stimuli - CORRECT
  All living organisms, from prokaryotes to eukaryotes show irritability i.e. the ability to sense their environment and respond to it.
  Plants and animals respond to external stimuli like light, temperature, water, etc.
  All organisms are conscious of their external environment.
  Thus we can consider, response to external stimuli as a defining property of living organisms.
• Option 4: Reproduction - INCORRECT
  Reproduction is one of the characteristics of living organisms.
  Reproduction refers to the production of offspring.
  Organisms can reproduce either sexually or asexually to give rise to offspring.
  However, reproduction cannot be regarded as a defining property because there are some cases where living organisms do not reproduce.
  Sterile worker bees, hybrids like a mule, liger, infertile human couples, etc. are some instances where living organisms cannot reproduce.

So from the above-given information, the correct answer is option 3.

Additional Information

• Apart from "response to stimuli", another defining property of a living organism is metabolism.
• Metabolism takes place in every living organism.
• Non-living objects do not show metabolism.

Concept:

• Viruses are non-cellular organisms that are characterized by having an inert crystalline structure outside the living cells.
• The name virus was given by Pasteur D. J. Ivanowsky (1892), who recognized certain microbes as the causative agent of the mosaic disease of tobacco.
• Viruses when infecting a cell and take over the machinery of the host cell to replicate themselves and kill the host.
• These are obligate parasites.
• The virus contains genetic material, that could be either RNA or DNA.
• There is no cell wall, membrane, or cytoplasm in viruses.
• It has a covering of proteins and this covering is called the capsid.

Key Points

• Viruses are called wandering genes because nucleic acid is the only active part of a virus.
• The infectivity of the virus is due to nucleic acid, as the virus is a nucleoprotein and the genetic material is infectious.
• The genetic material can replicate in the host cells.
• The host specificity of viruses is determined by the protein coat. 
• The protein coat is called the capsid made of small subunits namely capsomeres.
• These capsomeres are arranged in helical or polyhedral geometric forms.
• Capsomeres protect the nucleic acids.

Additional Information

• Viruses that infect plants have single-stranded RNA and viruses that infect animals have either single or double-stranded RNA or double-stranded DNA.
• Viruses cause diseases like mumps, smallpox, herpes, influenza, AIDS, etc.
• In plants, the symptoms can be mosaic formation, leaf rolling and curling, yellowing, and vein clearing, dwarfing and stunted growth, etc.

Hence, the correct option is (3).

Concept:

• Infectious agents are organisms that can cause disease or an infection in another organism like humans.
• Fungi, viruses, bacteria, and viroid are some examples of infectious agents.

Explanation:

• Virus - 
  • ​Viruses are acellular organisms that have either DNA or RNA as their genetic material.
  • The genetic material could be either a single or double-stranded RNA or double-stranded DNA.
  • Viruses show the presence of a protein coat called capsid surrounding their genetic material.
  • Thus the body of a virus consists of just a strand of nucleic acid( genetic material) surrounded by a protein coat.
  • Viruses are non-living organisms that require a host body to duplicate.
  • Once inside a host cell, they take charge of the cellular machinery and duplicate themselves.
  • Viruses are pathogenic organisms that cause several diseases in living organisms including humans.
  • AIDS, mumps, chicken pox, etc. are some of the diseases caused by viruses.
• Viroid - 
  • ​Viroid is a type of infectious agent that can cause infection in only plants like a coconut tree.
  • Viroids have small single-stranded RNA as their genetic material without any protein coat.
  • Viroid replicates at the expense of the host plant it infects.
  • Due to the absence of a protein coat, viroid lacks attachment proteins and hence cannot identify and penetrate host cells.
  • Viroid can enter a host cell only if the membrane of the host cell is damaged.
  • Due to this viroid infect plant cells that are already damaged by other agents like insects.
• From the above-given information, the major difference between a virus and a viroid is the presence or absence of a protein coat.
• Viruses have a protein coat surrounding their genetic material whereas viroids do not have a protein coat.

So the correct answer is option 1.

Concept:

• There are innumerable species of plants and animals and other organisms inhabiting the surface of the earth.
• To identify and study these species, it is necessary to develop a mechanism that has a universal application.
• Carl Linnaeus divided all the life forms present on the earth into two groups based on their mode of nutrition.
• He gave the two Kingdom System which includes - Kingdom Plantae and Kingdom Animalia.
• However, this system of classification was inadequate due to the vast majority of organisms found on earth.
• Later on, R.H. Whittaker proposed the Five Kingdom System of Classification.
• According to R.H. Whittaker's Five Kingdom system, the living organisms are divided into the following Kingdoms - 
  • Kingdom Monera
  • Kingdom Protista
  • Kingdom Plantae
  • Kingdom Fungi
  • Kingdom Animalia

Explanation:

• Option 1: Monera - INCORRECT
  • Kingdom Monera includes all the unicellular prokaryotic organisms.
  • Archaebacteria and Eubacteria are grouped under Kingdom Monera.
  • These organisms are found in all types of environments.
  • Examples: Cyanobacteria, Streptococcus, Lactobacillus, etc.
• Option 2: Protista - CORRECT
  • ​Kingdom Protista includes all the unicellular eukaryotic organisms.
  • This Kingdom shows a link with the remaining eukaryotic Kingdoms - Fungi, Plantae, and Animalia.
  • Examples: Paramecium, Amoeba, Euglena, etc.
• Option 3: Fungi - INCORRECT
  • ​Kingdom Fungi include multicellular eukaryotic organisms (except for yeast which is unicellular).
  • The organisms belonging to this Kingdom are mainly heterotrophs.
  • Examples: Agaricus bisporus, Saccharomyces cerevisiae, Rhizopus, etc.
• Option 4: Bacteria - INCORRECT
  • ​Bacteria are a group of organisms belonging to Kingdom Monera.
  • These are unicellular prokaryotic organisms.
  • Examples: Salmonella, Pseudomonas, Escherichia, Clostridium, etc. are some of the genera of bacteria.

So from the above-given information, the correct answer is option 2.

Concept:

• The ecosystem consists of all the biotic factors (plants, animals, and microorganisms) and the physical environment (abiotic factors) that they interact with.
• The organisms that live together interact with each other and influence each other's life directly or indirectly.
• Vital processes like growth, survival, nutrition and reproduction are depended on these interactions.
• The major interactions seen among the organisms in an ecosystem are - Predation, Parasitism, Commensalism, Amensalism, Mutualism, Competition, etc.

Explanation:

• The interaction between roots of higher plants and fungi is an example of mutualism.
• In mutualism, both the organisms involved are benefitted from this type of interaction.
• It is a (+/+) kind of interaction.
• Mutualism is an interaction between two organisms of different species where both organisms are benefitted.
• Neither of the two organisms can survive separately.

Option 1: Lichen - INCORRECT

• ​Lichen is an example of mutualistic interaction between two organisms.
• The association in a lichen is between algae and fungi.

Option 2: Fern - INCORRECT

• Fern is a non-flowering vascular plant.
• Ferns are pteridophytes. 

Option 3: Mycorrhiza - CORRECT

• Mycorrhizae are fungi that live in symbiotic association with plants.
• They are found either inside the roots or on the surface of higher plants.
• The mycorrhizae form mycorrhizal structures inside of the roots or on the surface of the plant for symbiotic association.
• In this association, both the fungi and plant benefit.
• Thus the association between roots of higher plants and fungi is called mycorrhiza.

Option 4: BGA - INCORRECT

• ​BGA - Blue-green algae.
• These are photosynthetic bacteria. These are unicellular, colonial, or filamentous in structure.

So from the above-given information, the correct answer is option 3.

Concept:

• According to R.H. Whittaker's Five Kingdom system, the living organisms are divided into the following Kingdoms - 
  • Kingdom Monera
  • Kingdom Protista
  • Kingdom Plantae
  • Kingdom Fungi
  • Kingdom Animalia
• Kingdom Monera includes unicellular prokaryotic organisms. E.g.- Salmonella
• Kingdom Protista includes unicellular eukaryotic organisms. E.g.- Amoeba
• Kingdom Plantae includes multicellular eukaryotic organisms. Includes autotrophs, semi-autotrophs, and insectivorous plants.
• Kingdom Fungi include multicellular eukaryotic organisms. These are mainly heterotrophs. E.g.- Rhizopus
• Kingdom Animalia includes multicellular eukaryotes that are heterotrophs. These organisms have adapted to holozoic nutrition. E.g.- Human beings

Explanation:

• Virus - 
  • ​Viruses are acellular or non-cellular organisms that have either DNA or RNA as their genetic material.
  • They have an inert crystalline structure outside the living cell.
  • The genetic material could be either a single or double-stranded RNA or double-stranded DNA.
  • Viruses show the presence of a protein coat called capsid surrounding their genetic material.
  • Thus the body of a virus consists of just a strand of nucleic acid (genetic material) surrounded by a protein coat.
  • Viruses are non-living organisms that require a host body to duplicate. They are obligate parasites.
  • Once inside a host cell, they take charge of the cellular machinery and duplicate themselves.
  • Viruses are not considered a "truly living" organism as they do not possess a cellular structure i.e. they are acellular.
  • Since they are not considered living organisms, viruses were not placed in any of the Kingdoms as proposed by R.H. Whittaker.
  • Viruses are pathogenic organisms that cause several diseases in living organisms including humans.
  • AIDS, mumps, chicken pox, etc. are some of the diseases caused by viruses in humans.
  • In plants, leaf rolling and curling, yellowing and vein clearing, dwarfing and stunted growth, etc. are caused due to viruses.

So from the above-given information, the correct answer is option 4.