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.
Correct Answer :
C. bacterial multiplication is reduced.
Food can be kept for a longer time in cold house than in normal condition because bacterial multiplication is reduced in cold house.
Related Questions
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.
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
The symbiotic association of fungi and algae is called
lichen
mycorrhiza
rhizome
endomycorrhiza
Which of the following kingdom does not have nuclear membrane ?
Protista
Fungi
Monera
Plantae
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
Protists are
single-celled eukaryotes.
multicellular eukaryotes.
single-celled prokaryotes.
single-celled akaryote.
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
Match the scientists given in column I with their discovery given in column II and choose the correct option.
| Column-I | Column-II |
|---|---|
| (Scientists) | (Discovery) |
| A. Ernst Mayr | I. Discovered Viroids |
| B. Whittaker | II. Gave the name virus |
| C. Pasteur | III. Proposed five kingdom classification |
| D. Diener | IV. Darwin of the 20th century |
A IV, B III, C II, D I
A III, B IV, C II, D I
A II, B III, C IV, D I
A I, B II, C III, D IV
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
When a moist bread is kept exposed in air, it becomes mouldy and black because
spores are present in the water.
spores are present in the bread.
spores are present in the air.
the bread decomposes.
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
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
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.
Which group of fungi is commonly known as imperfect fungi ?
Phycomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes
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.
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.
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.
Dikaryon formation is the characteristic feature of
ascomycetes and basidiomycetes.
phycomycetes and basidiomycetes.
ascomycetes and phycomycetes.
phycomycetes and zygomycetes.
Which class of fungi lacks sex organs but the process of plasmogamy is brought about by fusion of two vegetative or somatic cells of different strains or genotypes?
Sac fungi
Bracket fungi
Imperfect fungi
Phycomycetes
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
Which of the following are the characters of dinoflagellates?
(i) They are planktonic golden yellow algae with soap box like structure.
(ii) They are marine red biflagellated protista.
(iii) They appear yellow, green, brown, blue and red in colour.
(iv) They are biflagellated organisms with pellicle.
(v) They are saprophytic (or) parasitic unicellular forms.
(ii) and (iii)
(ii) and (v)
(i), (ii) and (iii)
(ii), (iv) and (v)
Which of the following statement is correct for both bluegreen algae and bacteria ?
Both show anaerobic respiration.
Both have chlorophyll pigment.
Both are devoid of true nucleus.
None of the above
Fungi show asexual reproduction by all of the following kinds of spores except
conidia
oospores
sporangiospores
zoospores
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.
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
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 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.
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
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
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