Bacteria are found to be primitive organisms because they
are small, microscopic which are not seen with naked eye.
cause serious diseases to human being, domesticated animals and crop plants.
produce endospores which are very resistant to adverse conditions.
possess incipient nucleus and show amitotic division.
Correct Answer :
D. possess incipient nucleus and show amitotic division.
Bacteria are microscopic organisms whose single cells have neither a membrane-enclosed nucleus nor other membraneenclosed organelles like mitochondria and chloroplasts. Bacteria are found to be primitive organisms because they possess incipient nucleus and shows amitotic division.
Related Questions
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
Which group of fungi is commonly known as imperfect fungi ?
Phycomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes
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.
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
Clamp connection is found in
basidiomycetes
ascomycetes
saccharomycetes
haplomycetes
Select the correct match from the given option.
Occurrence of dikaryotic stage - ascomycetes and basidiomycetes.
Saprophytes - They are autotrophic and absorb soluble organic matter from dead substrates.
Vegetative mean of reproduction in fungi - fragmentation, budding and sporangiophores.
Steps involved in asexual cycle of fungi - plasmogamy, karyogamy and meiosis in zygote resulting in haploid spores.
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
A virus can be considered a living organism because it
responds to touch stimulus
respires
reproduces (inside the host)
can cause disease
Match column I with column II and choose the correct option.
| Column I | Column II |
|---|---|
| A. Mycoplasma | (i) Nitrogen fixing cells |
| B. Decomposers | (ii) Blue green algae |
| C. Methanogens | (iii) Production of methane |
| D. Heterocysts | (iv) Most abundant heterotrophs |
| E. Cyanobacteria | (v) Pathogenic in plants and animals |
A-(i) B-(ii) C-(iii) D-(iv) E-(v)
A-(iii) B-(v) C-(ii) D-(iv) E-(i)
A-(iii) B-(i) C-(v) D-(ii) E-(iv)
A-(v) B-(iv) C-(iii) D-(i) E-(ii)
Bladderwort and Venus fly trap are examples of
insectivorous plants
parasitic plants
N2 rich plants
aquatic plants
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 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
T. O. Diener discovered a new infectious agent that was smaller than viruses and have the following characteristics.
(i) It causes potato spindle tuber disease.
(ii) It has free RNA.
(iii) Molecular weight of RNA is low.
Identify the infections agent.
Viruses
Viroids
Virion
Mycoplasma
Which of the following statement is incorrect ?
TMV has a double-stranded RNA molecule.
Most plant viruses are RNA viruses.
The bacteriophage has a double-stranded DNA molecule.
Most animal viruses are DNA viruses.
Which of the following statement(s) is/are correct ?
(i) Reproduction in fungi can take place by vegetative means fragmentation, fission and budding.
(ii) Fusion of two nuclei is called plasmogamy.
(iii) Fusion of protoplasms between two motile or nonmotile gametes is called karyogamy.
(iv) Meiosis in zygote results in diploid spores.
Only (i)
Both (ii) and (iii)
(ii), (iii) and (iv)
All of these
Which of the following pairs comes under the group chrysophytes ?
Diatoms and Euglena
Euglena and Trypanosoma
Diatoms and Desmids
Gonyaulax and Desmids
How many bacteria are produced in four hours if a bacterium divides once in half an hour ?
8
64
16
256
How many organisms in the list given below are autotrophs? Lactobacillus, Nostoc, Chara, Nitrosomonas, Nitrobacter, Streptomyces, Saccharomyces, Trypanosomes, Porphyra, Wolffia
Four
Five
Six
Three
Which one of the following statement is correct for archaea?
Archaea resemble eukaryotes in all respects.
Archaea have some novel features that are absent in other prokaryotes and eukaryotes.
Archaea completely differ from both prokaryotes and eukaryotes.
Archaea completely differ from prokaryotes.
Consider the following statements with respect to characteristic features of the kingdom.
(i) In animalia, the mode of nutrition is autotrophic.
(ii) In monera, the nuclear membrane is present.
(iii) In protista, the cell type is prokaryotic.
(iv) In plantae, the cell wall is present.
Of the above statements, which one is correct ?
(i) only
(ii) only
(iii) only
(iv) only
Dikaryon formation is the characteristic feature of
ascomycetes and basidiomycetes.
phycomycetes and basidiomycetes.
ascomycetes and phycomycetes.
phycomycetes and zygomycetes.
Protozons are not included in kingdom animalia because they are
mostly asymmetrical.
unicellular eukaryotes.
heterotrophic in nature.
multicellular prokaryotes.
Which of the following is not a viral disease ?
AIDS and mumps
Small pox and herpes
Influenza
Cholera
Fungi show asexual reproduction by all of the following kinds of spores except
conidia
oospores
sporangiospores
zoospores
The given statements are some characters of a particular group of Kingdom protista.
(i) Most of them are fresh water organisms found in standing water.
(ii) They have a protein rich layer (called pellicle) which makes their body flexible.
(iii) They have two flagella, a short and a long one.
(iv) Though they are photosynthetic in the presence of sunlight, but in the absence of sunlight they behave like heterotrophs by predating on other smaller organisms.
Identify the correct group on the basis of these characters.
Protozoans
Chrysophytes
Slime moulds
Euglenoids
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
Match column I (Kingdom) with column II (Class) and select the correct options
| Column-I | Column-II |
|---|---|
| (Kingdom) | (Class) |
| A. Plantae | I. Archaebacteria |
| B. Fungi | II. Euglenoids |
| C. Protista | III. Phycomycetes |
| D. Monera | IV. Algae |
A IV, B III, C II, D I
A I, B II, C III, D IV
A III, B IV, C II, D I
A IV, B II, C III, D I
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 the type of protozoans given in column-I with their examples given in column-II and choose the correct option.
| Column-I | Column-II |
|---|---|
| (Type of Protozoans) | (Examples) |
| A. Amoeboid protozoans | I. Paramecium |
| B. Ciliated protozoans | II. Plasmodium |
| C. Flagellated protozoans | III. Amoeba |
| D. Sporozoans | IV. Trypanosoma |
A I; B III; C IV; D II
A III; B I; C II; D IV
A III; B I; C IV; D II
A III; B IV; C I; D II