How many bacteria are produced in four hours if a bacterium divides once in half an hour ?
8
64
16
256
Correct Answer :
D. 256
Related Questions
Match the terms given in column-I with their examples given in column-II and choose the correct option
| Column-I | Column-II |
|---|---|
| (Terms) | (Examples) |
| A. Ascus | I. Spirulina |
| B. Basidium | II. Penicillium |
| C. Protista | III. Agaricus |
| D. Cyanobacteria | IV. Euglena |
| E. Animalia | V. Sponges |
A II, B III, C IV, D V, E I
A I, B II, C III, D V, E IV
A II, B V, C III, D I, E IV
A II, B III, C IV, D I, E V
Bacteria lack alternation of generation because there is
neither syngamy nor reduction division.
no distinct chromosomes.
no conjugation.
no exchange of genetic material.
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.
In some viruses, RNA is present instead of DNA indicating that
their nucleic acid must combine with host DNA before replication.
they cannot replicate.
there is no hereditary information.
RNA can transfer heredity material.
The subunit of capsid is called
core
nucleotide
amino acid
capsomere
Lichens indicate SO2 pollution because they
show association between algae and fungi.
grow faster than others.
are sensitive to SO2.
flourish in SO2 rich environment.
Dikaryon formation is the characteristic feature of
ascomycetes and basidiomycetes.
phycomycetes and basidiomycetes.
ascomycetes and phycomycetes.
phycomycetes and zygomycetes.
Which of the following pairs comes under the group chrysophytes ?
Diatoms and Euglena
Euglena and Trypanosoma
Diatoms and Desmids
Gonyaulax and Desmids
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.
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
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)
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
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.
Which group of fungi is commonly known as imperfect fungi ?
Phycomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes
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 pair is correctly matched ?
Fungi Saprophytic parasitic mode of nutrition.
Monera Nuclear membrane is present.
Plantae Cell wall is made up of cellulose.
Animalia Cell wall is absent.
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.
Bacteria were regarded to be plants because
some of them are green in colour.
they are present every where.
some of them cannot move.
they have a rigid cell wall.
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
Which of the following is smallest living cell and can live without oxygen ?
Mycoplasma
Mycorrhiza
Euglena
Trypanosoma
The genetic material of virus includes
only RNA.
only DNA.
RNA and DNA both
RNA or DNA i.e. one nucleic acid in a virus.
Match the characters given in column I with their examples given in column II.
| Column I | Column II |
|---|---|
| A. Long slender thread | (i) Lichen like structures |
| B. Association of fungi with | (ii) Mycorrhiza roots of higher plants |
| C. Parasitic fungi on mustard | (iii) Neurospora |
| D. Fungi extensively used in | (iv) Albugo biochemical and genetic work |
| E. An association in which | (v) Hyphae algal component is called phycobiont |
A-(v) B-(ii) C-(iv) D-(iii) E-(i)
A-(iii) B-(i) C-(iv) D-(ii) E-(v)
A-(ii) B-(i) C-(iii) D-(v) E-(iv)
A-(iii) B-(ii) C-(iv) D-(i) E-(v)
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
Which of the following characteristic(s) is used by Whittaker for the classification of organisms ?
Mode of nutrition
Thallus organisation
Phylogenetic relationships
All of the above
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
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
Identify the basis of classification of fungi into phycomycetes, ascomycetes, basidiomycetes and deuteromycetes.
i. Fruiting bodies
ii. Nature of habitat
iii. Morphology of mycelium
iv. Mode of spore formation
i & ii only
ii & iii only
i, ii, & iv only
All of these
Which of the following is used extensively in biochemical and genetic work ?
Agaricus
Alternaria
Neurospora
Mucor
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
Which of the following is a parasitic fungi on the mustard plant ?
Albugo
Puccinia
Yeast
Ustilago