The figure given below shows the structure of a bacteriophage. Identify its parts labelled as A, B, C and D.
A - Tail fibres B - Head C - Sheath D - Collar
A - Sheath B - Collar C - Head D - Tail fibres
A - Head B - Sheath C - Collar D - Tail fibres
A - Collar B - Tail fibres C - Head D - Sheath
Correct Answer :
C. A - Head B - Sheath C - Collar D - Tail fibres
The given diagram is of bacteriophage (viruses that infect the bacteria). They have tadpole-like structure, i.e., with head and tail. Nucleic acid generally DNA is present inside the head. Tail is having hollow core end is surrounded by tail sheath. At the end of tail, end plate is present to which tail fibres are attached.
Related Questions
Which group of fungi is commonly known as imperfect fungi ?
Phycomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes
Which of the following is not a viral disease ?
AIDS and mumps
Small pox and herpes
Influenza
Cholera
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
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.
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
Ustilago causes plant diseases (called smuts) because
they parasitize on cereals.
they lack mycelium.
they develop sooty masses of spores.
their affected parts becomes completely black.
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 ?
(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 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.
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 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 not correct for methanogens?
They are archaebacteria.
They live in marshy areas.
Methane is their preferred carbon source.
They are present in guts of several ruminant animals (cow, buffaloes) and produce biogas (CH4) from the dung of these animals.
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
Bladderwort and Venus fly trap are examples of
insectivorous plants
parasitic plants
N2 rich plants
aquatic plants
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)
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 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.
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
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.
Match the class of fungi given in column-I with their common name given in column-II and select the correct option.
| Column-I | Column-II |
|---|---|
| (Class of fungi) | (Common name) |
| A. Phycomycetes | I. Sac fungi |
| B. Ascomycetes | II. Algal fungi |
| C. Basidiomycetes | III. Fungi imperfecti |
| D. Deuteromycetes | IV. Club fungi |
A II, B I, C IV, D III
A II, B IV, C I, D III
A IV, B I, C II, D III
A IV, B III, C II, D I
Which of the following is a parasitic fungi on the mustard plant ?
Albugo
Puccinia
Yeast
Ustilago
Which of the following processes involved in the reproduction of protists ?
Binary fission and budding
Cell fusion and zygote formation
Spore formation and cyst formation
All of the above
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 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 class of fungi is being described by the given statements ?
(i) They are found in aquatic habitats and on decaying wood in moist and damp places.
(ii) Mycelium is aseptate and coenocytic.
(iii) Asexual reproduction takes place by zoospores (motile) or by aplanospores (non-motile).
(iv) Some common examples are Mucor, Rhizopus and Albugo.
Ascomycetes
Phycomycetes
Basidiomycetes
Deuteromycetes
Match column-I (Characters/feature) with column-II (examples) and choose the correct option.
| Column-I | Column-II |
|---|---|
| (Characters/features) | (Examples) |
| A. Red dinoflagellates | I. Rhizopus |
| B. Unicellular fungi used to | II. Gonyaulax make bread and beer |
| C. Source of antibiotics | III. Yeast |
| D. Bread mould | IV. Penicillium |
A III; B II; C I; D IV
A II; B III; C I; D IV
A II; B III; C IV; D I
A II; B IV; C III; D I
The symbiotic association of fungi and algae is called
lichen
mycorrhiza
rhizome
endomycorrhiza
Which of the following is an example of amoeboid protozoans ?
Trypanosoma
Paramecium
Gonyaulax
Entamoeba
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 characteristic(s) is used by Whittaker for the classification of organisms ?
Mode of nutrition
Thallus organisation
Phylogenetic relationships
All of the above