A virus can be considered a living organism because it
responds to touch stimulus
respires
reproduces (inside the host)
can cause disease
Correct Answer :
C. reproduces (inside the host)
A virus is an infective agent that typically consists of a nucleic acid molecule in a protein coat. It is too small to be seen by light microscopy, and is able to multiply only within the living cells of a host. It can be considered living organisms because it reproduces inside the host cell.
Related Questions
Which of the following is used extensively in biochemical and genetic work ?
Agaricus
Alternaria
Neurospora
Mucor
Which one single organism or the pair of organisms is correctly assigned to its taxonomic group?
Paramecium and Plasmodium belong to the same kingdom as that of Penicillium.
Lichen is a composite organism formed from the symbiotic association of an alga and a protozoan.
Yeast used in making bread and beer is a fungus.
Nostoc and Anabaena are examples of protista.
The bacteria which oxidize various inorganic substances and use the released energy for their ATP production are called _______________.
Archaebacteria
Heterotrophic bacteria
Photosynthetic autotrophic bacteria
Chemosynthetic autotrophic bacteria
Which of the following is not a viral disease ?
AIDS and mumps
Small pox and herpes
Influenza
Cholera
Bacteria and yeast are similar in all the following features except that
both are unicellular.
both are prokaryotes.
both are capable of causing fermentation.
both produce spores.
Mycorrhizae are useful for plants because they
fix atmospheric nitrogen.
enhance absorption of nutrients from the soil.
kill insects and pathogen.
provide resistance against abiotic stresses.
A virus can be considered a living organism because it
responds to touch stimulus
respires
reproduces (inside the host)
can cause disease
Bladderwort and Venus fly trap are examples of
insectivorous plants
parasitic plants
N2 rich plants
aquatic plants
Choose the correct statements (i v) regarding mycoplasma
(i) Mycoplasma has no cell wall.
(ii) Mycoplasma is the smallest living organism.
(iii) Mycoplasma cannot survive without O2.
(iv) Mycoplasma are pathogenic in animals and plants.
(v) A sort of sexual reproduction occurs in bacterium by adopting a primitive DNA transfer from one bacterium to the other.
Only (iii)
(i), (iii) and (v)
(i), (ii), (iv), and (v)
All of the above
Chemosynthetic autotrophic bacteria are named so because
they oxidize various inorganic substances such as nitrates, nitrites and ammonia and use the released energy for their ATP production.
they oxidize various organic substances and use the released energy for their ATP production.
both (a) and (b)
none of these
Bacteria lack alternation of generation because there is
neither syngamy nor reduction division.
no distinct chromosomes.
no conjugation.
no exchange of genetic material.
The given figure shows some labelled structure as A, B, C and D. In which structure the protein coat that encloses the nucleic acid is present?
A
B
C sheath
D tail fibres
Which of the following groups of protozoan is not correctly matched with its feature?
Amoeboid - Marine forms have silica shells on their surface.
Flagellated - Either free living or parasitic.
Ciliated - Actively moving organisms due to presence of cilia.
Sporozoans - Move and capture their prey with the help of false feet.
Which of the following statement is correct for dinoflagellates flagella ?
A single flagellum lies in the transverse groove between the cell plates.
A single flagellum lies in the longitudinal groove between the cell plates.
Two flagella, one lies longitudinally and the other transversely in a furrow between the wall plates.
Flagella are absent.
Match column I (containing fungus name) with column II (common name) and choose the correct options.
| Column-I | Column-II |
|---|---|
| (Fungus name) | (Commonly called) |
| A. Puccinia | I. Yeast |
| B. Ustilago | II. Mushroom |
| C. Agaricus | III. Smut fungus |
| D. Saccharomyces | IV. Rust fungus |
A I, B II, C III, D IV
A II, B III, C IV, D I
A III, B IV, C I, D II
A IV, B III, C II, D I
The most abundant prokaryotes helpful to humans in making curd from milk and in production of antibiotics are the ones categorised as
cyanobacteria
archaebacteria
chemosynthetic autotrophs
heterotrophic bacteria
Assume that two normal hyphal cells of different fungal mating types unite. After a period of time, the cell between these cells will dissolve producing a
mycelium
fruiting body
zygote
dikaryotic cell, which is also heterokaryotic
Which of the following statement is/ are correct for bacteria ?
They are the members of the kingdom monera.
They live in extreme habitats such as hot springs, deserts, snow and deep oceans.
They show the most extensive metabolic diversity.
All of the above
Which of the following kingdom does not have nuclear membrane ?
Protista
Fungi
Monera
Plantae
Fungi show asexual reproduction by all of the following kinds of spores except
conidia
oospores
sporangiospores
zoospores
The given figure shows the structure of filamentous blue green algae, Nostoc with a structure marked as X. Select the option which shows the correct identification of the X with its feature.
Spores - Reproduction
Heterocysts - Nitrogen fixation
Pellicle - Recycling of nutrition
Mucilaginous sheath - Photosynthesis
Read the following statements and answer the question.
(i) Some members are saprophytes or parasites while a large number of them are decomposers of litter and help in mineral cycling.
(ii) They reproduce only by asexual spores known as conidia.
(iii) Mycelium is septate and branched.
(iv) Alternaria, Colletotrichum and Trichoderma are examples of this class.
Which of the following class of fungi is being described by the above statements ?
Phycomycetes
Deuteromycetes
Basidiomycetes
Ascomycetes
Protista includes
unicellular eukaryotes with well-defined nucleus only.
unicellular prokaryotes with membrane bound organelles.
unicellular eukaryotes with well-defined nucleus and membrane bound organelles.
both unicellular and multicellular eukaryotes with welldefined nucleus and membrane bound organelles.
Which of the following statement(s) is/are correct about ascomycetes ?
(i) Neurospora, which is used in biochemical and genetic work is a member of this class.
(ii) They are mostly multicellular, e.g., Yeast, or rarely unicellular, e.g., Penicillium.
(iii) They are saprophytic, decomposers, parasitic or coprophilous.
(iv) Some examples are Aspergillus, Claviceps and Neurospora.
Both (i) and (ii)
Only (ii)
(i), (iii) and (iv)
All of these
Read the following statements and answer the question given below
(i) They are saprophytic protists.
(ii) Under suitable conditions, they form an aggregation (called plasmodium) which may grow and spread over several feet.
(iii) During unfavourable conditions, the plasmodium differentiates and forms fruiting bodies bearing spores at their tips.
Which of the following class of protists is being described by the above statements ?
Euglenoids
Dinoflagellates
Slime moulds
Protozoans
Which of the following is the correct sequence of three steps in the sexual cycle of fungi?
Mitosis -> Meiosis -> Fertilization
Plasmogamy -> Karyogamy -> Meiosis
Mitosis -> Plasmogamy -> Karyogamy
Karyogamy -> Plasmogamy -> Meiosis
Which scientist classify plants into trees, shrubs and herbs & animals into two groups having red blood cells and without red blood cells?
Aristotle
R. H. Whittaker
D. J. Ivanowsky
W. M. Stanley
Why food can be kept for a longer time in cold house than in normal conditions ? Because,
insect cannot enter.
bacterial multiplication stops.
bacterial multiplication is reduced.
there is plasmolysis at low temperature.
The given characters are seen in which of the following group?
(i) Unicellular, colonial, filamentous, marine or terrestrial forms.
(ii) The colonies are surrounded by a gelatinous sheath.
(iii) Some can fix atmospheric nitrogen in specialized cells called heterocysts.
(iv) They often form blooms in water bodies.
Archaebacteria
Cyanobacteria
Chrysophytes
Dinoflagellates
Which of the following is an example of amoeboid protozoans ?
Trypanosoma
Paramecium
Gonyaulax
Entamoeba