Page 1
Solution
1. (a)
Protista include all unicellular and colonial
eukaryotes except those of green and red algae.
The protistan cells are typically eukaryotic having
membrane bound organelles like mitochondria,
chloroplasts, Golgi bodies, endoplasmic
reticulum, nucleus, etc. Protista is commonly
known as kingdom of unicellular eukaryotes.
Kingdom Fungi contains achlorophyllous, spore
producing, heterotrophic, multicellular or
multinucleate eukaryotic organisms (unicellular
yeasts are also included amongst fungi because
their sexual reproduction is similar to that of
some fungi). Monerans are basically unicellular
prokaryotes. Archaea (ancient bacteria) are also
a type of monerans which live in primitive
environment like high temperature, high salt
content, acidic pH, etc.
2. (b)
Streptococcus is a bacteria which is included
under Kingdom Monera. Monerans have
prokaryotic cell organisation in which membrane
bound organelles like mitochondria, E.R., Golgi
bodies, etc., are absent. All the other three i.e.,
Saccharomyces (a fungus), Chlamydomonas (an
algae) and Plasmodium (a protozoan protist) are
eukaryotes containing true membrane bound
organelles.
3. (b)
Association between roots of higher plants, e.g.,
pine, birch and fungal hyphae is called
mycorrhiza. It exhibits the phenomenon of
symbiosis. Here both the organisms in association
are mutually benefitted. In this, fungal hyphae
take nutrition from the plant and in return increase
surface area for absorption of water and minerals
for the plant.
4. (c)
Pseudopodia is the locomotory organ in amoeboid
protozoans, e.g., Amoeba. Flagellated protozoans
possess flagella for locomotion, e.g., Trypanosoma.
In sporozoans, locomotory organelles (cilia, flagella,
pseudopodia, etc.) are absent, e.g., Plasmodium.
Ciliated protozoans possess cilia as locomotory
organelles, e.g., Paramecium.
5. (a)
Both statements are correct.
6. (d)
Penicillium and Agaricus are fungi while Volvox
is an alga. All three are eukaryotes thus have a
membrane bound nucleus. Nostoc is a
cyanobacterium, i.e., prokaryote, so it lacks true
nucleus, thus nuclear membrane is absent.
7. (b)
The true fungi or the eumycetes are special types
of achlorophyllous thallophytic organisms living a
parasitic or a saprophytic mode of existence; they
are always heterophytes and never autophytes. They
depend on others for food, but all other groups as
algae, bryophytes and pteridophytes are chlorophyll
containing green plants that are autotrophic.
8. (b)
Kingdom Monera consists of prokaryotic
organisms, characterised by absence of nuclear
envelope around nucleus and absence of
membrane-bound cell organelles.
9. (b)
Gorgonia (sea-fan) is an animal belonging to
Phylum Coelenterata. All animals lack cell wall.
10. (b)
Viroids are free RNA particles that lack protein
coat. They are infectious agents smaller than
viruses.
11. (b)
All prokaryotic organisms come under Kingdom
Monera. Escherichia coli is a bacterium. Monera
includes bacteria, mycoplasmas, cyanobacteria (blue
green algae) and actinomycetes.
12. (b)
Diatoms are the most common form of
phytoplankton in the ocean. They have the
pigment chlorophyll which helps in photosynthesis.
Since, they are the primary producers of the
aquatic food chain and the marine ecosystem
depends on them. They are called chief producers
in the oceans.
13. (b)
Bacteria reproduce mainly by fission. Sometimes,
under unfavourable conditions, they produce
spores. They also reproduce by a sort of sexual
reproduction by adopting a primitive type of DNA
transfer from one bacterium to the other.
Page 2
Solution
1. (a)
Protista include all unicellular and colonial
eukaryotes except those of green and red algae.
The protistan cells are typically eukaryotic having
membrane bound organelles like mitochondria,
chloroplasts, Golgi bodies, endoplasmic
reticulum, nucleus, etc. Protista is commonly
known as kingdom of unicellular eukaryotes.
Kingdom Fungi contains achlorophyllous, spore
producing, heterotrophic, multicellular or
multinucleate eukaryotic organisms (unicellular
yeasts are also included amongst fungi because
their sexual reproduction is similar to that of
some fungi). Monerans are basically unicellular
prokaryotes. Archaea (ancient bacteria) are also
a type of monerans which live in primitive
environment like high temperature, high salt
content, acidic pH, etc.
2. (b)
Streptococcus is a bacteria which is included
under Kingdom Monera. Monerans have
prokaryotic cell organisation in which membrane
bound organelles like mitochondria, E.R., Golgi
bodies, etc., are absent. All the other three i.e.,
Saccharomyces (a fungus), Chlamydomonas (an
algae) and Plasmodium (a protozoan protist) are
eukaryotes containing true membrane bound
organelles.
3. (b)
Association between roots of higher plants, e.g.,
pine, birch and fungal hyphae is called
mycorrhiza. It exhibits the phenomenon of
symbiosis. Here both the organisms in association
are mutually benefitted. In this, fungal hyphae
take nutrition from the plant and in return increase
surface area for absorption of water and minerals
for the plant.
4. (c)
Pseudopodia is the locomotory organ in amoeboid
protozoans, e.g., Amoeba. Flagellated protozoans
possess flagella for locomotion, e.g., Trypanosoma.
In sporozoans, locomotory organelles (cilia, flagella,
pseudopodia, etc.) are absent, e.g., Plasmodium.
Ciliated protozoans possess cilia as locomotory
organelles, e.g., Paramecium.
5. (a)
Both statements are correct.
6. (d)
Penicillium and Agaricus are fungi while Volvox
is an alga. All three are eukaryotes thus have a
membrane bound nucleus. Nostoc is a
cyanobacterium, i.e., prokaryote, so it lacks true
nucleus, thus nuclear membrane is absent.
7. (b)
The true fungi or the eumycetes are special types
of achlorophyllous thallophytic organisms living a
parasitic or a saprophytic mode of existence; they
are always heterophytes and never autophytes. They
depend on others for food, but all other groups as
algae, bryophytes and pteridophytes are chlorophyll
containing green plants that are autotrophic.
8. (b)
Kingdom Monera consists of prokaryotic
organisms, characterised by absence of nuclear
envelope around nucleus and absence of
membrane-bound cell organelles.
9. (b)
Gorgonia (sea-fan) is an animal belonging to
Phylum Coelenterata. All animals lack cell wall.
10. (b)
Viroids are free RNA particles that lack protein
coat. They are infectious agents smaller than
viruses.
11. (b)
All prokaryotic organisms come under Kingdom
Monera. Escherichia coli is a bacterium. Monera
includes bacteria, mycoplasmas, cyanobacteria (blue
green algae) and actinomycetes.
12. (b)
Diatoms are the most common form of
phytoplankton in the ocean. They have the
pigment chlorophyll which helps in photosynthesis.
Since, they are the primary producers of the
aquatic food chain and the marine ecosystem
depends on them. They are called chief producers
in the oceans.
13. (b)
Bacteria reproduce mainly by fission. Sometimes,
under unfavourable conditions, they produce
spores. They also reproduce by a sort of sexual
reproduction by adopting a primitive type of DNA
transfer from one bacterium to the other.
14. (a)
Diatoms are marine or freshwater unicellular
organisms which have cell walls composed of
pectin impregnated with silica and consisting of
two halves, one overlapping the other. The
siliceous frustules of diatoms do not decay easily.
15. (d)
Protista is a kingdom of unicellular eukaryotic
organisms. It includes photosynthetic protists
(dinoflagellates, chrysophytes and euglenoids),
consumer-decomposer protists (slime moulds) and
protozoan protists.
16. (c)
Chrysophytes include diatoms and desmids. The
body of diatoms is covered by a transparent siliceous
shell (silica deposited in cell wall) known as frustule.
The frustule is made of two valves, epitheca and
hypotheca, which fit together like a soap box.
17. (b)
Escherichia coli (bacterium) is not an example
of eukaryotic cell. It is a typical example of
prokaryotic cell.
18. (b)
NCERT figure 2.1
19. (b)
Blue green algae (cyanobacteria) are members
of kingdom monera.
20. (a)
Saprophytes are organisms that derive their
nutrition from dead or decaying organic matter.
Rhizopus, Aspergillus and mushrooms are some
of the examples of saprophytes.
In parasitism, only one species benefits (parasite)
and the interaction is harmful to the other species
(host). e.g: human liver fluke, malarial parasites
such as P. vivax, P. falciparum, etc.
Lichens is the mutualistic relationship between a
fungus and cyanobacteria. Similarly, mycorrhizae
is the symbiotic association between fungi and
the roots of higher plants.
21. (b)
Archaebacteria are found in most harsh habitats. Their
cell wall is adapted to tolerate extreme conditions
(wall contains protein and non-cellulosic
polysaccharides). Cell membranes are characterized
by the presence of branched chain lipids that make
them highly resistent to heat and low pH.
22. (c)
Methanogens are archaebacteria that live in
marshy area produce methane as a metabolic
byproduct in anoxic conditions. Methane is not
their preferred carbon source.
23. (b)
The sexual cycle involves the following three steps:
(i) Fusion of protoplasms between two motile or
non-motile gametes called plasmogamy.
(ii) Fusion of two nuclei called karyogamy.
(iii) Meiosis in zygote resulting in haploid spores.
24. (d)
Bacteria are microscopic organisms placed under
kingdom monera whose single cells have neither
a membrane-enclosed nucleus nor other
membrane enclosed organelles like mitochondria
and chloroplasts.
25. (c)
Chrysophytes belong to the kingdom protista.
Examples are diatoms and golden algae. Their
walls are embedded with silica and thus the walls
are indestructible.
26. (c)
Dinoflagellates are mostly marine and
photosynthetic organism. They appear yellow,
green, brown, blue or red depending on the main
pigments present in their cells. Most of them have
two flagella; one lies longitudinally and the other
transversely in a furrow between the cell plates.
27. (b)
Viroids cause potato spindle tuber disease
(PSTV), chrysanthemum stunt, citrus exocortis,
cucumber pale fruit etc. They cause persistent
infections, i.e., never recovered.
28. (d)
Kingdom animalia includes all heterotrophic,
multicellular complex eukaryotes. They depend
either upon plants or on other animals for their
food requirements. Kingdom monera includes
prokaryotic organisms lacking membrane bound
nucleus. Hence, nuclear membrane cannot be
found in Monera. Protista is a eukaryotic kingdom.
29. (b)
Chrysophytes are plant-like protists that can be
found in marine and freshwater environments
which are often low in calcium. There are three
main types of chrysophytes: diatoms
(bacillariophyta), golden-brown algae
(chrysophyceae), and yellow-green algae
(xanthophyceae).
Page 3
Solution
1. (a)
Protista include all unicellular and colonial
eukaryotes except those of green and red algae.
The protistan cells are typically eukaryotic having
membrane bound organelles like mitochondria,
chloroplasts, Golgi bodies, endoplasmic
reticulum, nucleus, etc. Protista is commonly
known as kingdom of unicellular eukaryotes.
Kingdom Fungi contains achlorophyllous, spore
producing, heterotrophic, multicellular or
multinucleate eukaryotic organisms (unicellular
yeasts are also included amongst fungi because
their sexual reproduction is similar to that of
some fungi). Monerans are basically unicellular
prokaryotes. Archaea (ancient bacteria) are also
a type of monerans which live in primitive
environment like high temperature, high salt
content, acidic pH, etc.
2. (b)
Streptococcus is a bacteria which is included
under Kingdom Monera. Monerans have
prokaryotic cell organisation in which membrane
bound organelles like mitochondria, E.R., Golgi
bodies, etc., are absent. All the other three i.e.,
Saccharomyces (a fungus), Chlamydomonas (an
algae) and Plasmodium (a protozoan protist) are
eukaryotes containing true membrane bound
organelles.
3. (b)
Association between roots of higher plants, e.g.,
pine, birch and fungal hyphae is called
mycorrhiza. It exhibits the phenomenon of
symbiosis. Here both the organisms in association
are mutually benefitted. In this, fungal hyphae
take nutrition from the plant and in return increase
surface area for absorption of water and minerals
for the plant.
4. (c)
Pseudopodia is the locomotory organ in amoeboid
protozoans, e.g., Amoeba. Flagellated protozoans
possess flagella for locomotion, e.g., Trypanosoma.
In sporozoans, locomotory organelles (cilia, flagella,
pseudopodia, etc.) are absent, e.g., Plasmodium.
Ciliated protozoans possess cilia as locomotory
organelles, e.g., Paramecium.
5. (a)
Both statements are correct.
6. (d)
Penicillium and Agaricus are fungi while Volvox
is an alga. All three are eukaryotes thus have a
membrane bound nucleus. Nostoc is a
cyanobacterium, i.e., prokaryote, so it lacks true
nucleus, thus nuclear membrane is absent.
7. (b)
The true fungi or the eumycetes are special types
of achlorophyllous thallophytic organisms living a
parasitic or a saprophytic mode of existence; they
are always heterophytes and never autophytes. They
depend on others for food, but all other groups as
algae, bryophytes and pteridophytes are chlorophyll
containing green plants that are autotrophic.
8. (b)
Kingdom Monera consists of prokaryotic
organisms, characterised by absence of nuclear
envelope around nucleus and absence of
membrane-bound cell organelles.
9. (b)
Gorgonia (sea-fan) is an animal belonging to
Phylum Coelenterata. All animals lack cell wall.
10. (b)
Viroids are free RNA particles that lack protein
coat. They are infectious agents smaller than
viruses.
11. (b)
All prokaryotic organisms come under Kingdom
Monera. Escherichia coli is a bacterium. Monera
includes bacteria, mycoplasmas, cyanobacteria (blue
green algae) and actinomycetes.
12. (b)
Diatoms are the most common form of
phytoplankton in the ocean. They have the
pigment chlorophyll which helps in photosynthesis.
Since, they are the primary producers of the
aquatic food chain and the marine ecosystem
depends on them. They are called chief producers
in the oceans.
13. (b)
Bacteria reproduce mainly by fission. Sometimes,
under unfavourable conditions, they produce
spores. They also reproduce by a sort of sexual
reproduction by adopting a primitive type of DNA
transfer from one bacterium to the other.
14. (a)
Diatoms are marine or freshwater unicellular
organisms which have cell walls composed of
pectin impregnated with silica and consisting of
two halves, one overlapping the other. The
siliceous frustules of diatoms do not decay easily.
15. (d)
Protista is a kingdom of unicellular eukaryotic
organisms. It includes photosynthetic protists
(dinoflagellates, chrysophytes and euglenoids),
consumer-decomposer protists (slime moulds) and
protozoan protists.
16. (c)
Chrysophytes include diatoms and desmids. The
body of diatoms is covered by a transparent siliceous
shell (silica deposited in cell wall) known as frustule.
The frustule is made of two valves, epitheca and
hypotheca, which fit together like a soap box.
17. (b)
Escherichia coli (bacterium) is not an example
of eukaryotic cell. It is a typical example of
prokaryotic cell.
18. (b)
NCERT figure 2.1
19. (b)
Blue green algae (cyanobacteria) are members
of kingdom monera.
20. (a)
Saprophytes are organisms that derive their
nutrition from dead or decaying organic matter.
Rhizopus, Aspergillus and mushrooms are some
of the examples of saprophytes.
In parasitism, only one species benefits (parasite)
and the interaction is harmful to the other species
(host). e.g: human liver fluke, malarial parasites
such as P. vivax, P. falciparum, etc.
Lichens is the mutualistic relationship between a
fungus and cyanobacteria. Similarly, mycorrhizae
is the symbiotic association between fungi and
the roots of higher plants.
21. (b)
Archaebacteria are found in most harsh habitats. Their
cell wall is adapted to tolerate extreme conditions
(wall contains protein and non-cellulosic
polysaccharides). Cell membranes are characterized
by the presence of branched chain lipids that make
them highly resistent to heat and low pH.
22. (c)
Methanogens are archaebacteria that live in
marshy area produce methane as a metabolic
byproduct in anoxic conditions. Methane is not
their preferred carbon source.
23. (b)
The sexual cycle involves the following three steps:
(i) Fusion of protoplasms between two motile or
non-motile gametes called plasmogamy.
(ii) Fusion of two nuclei called karyogamy.
(iii) Meiosis in zygote resulting in haploid spores.
24. (d)
Bacteria are microscopic organisms placed under
kingdom monera whose single cells have neither
a membrane-enclosed nucleus nor other
membrane enclosed organelles like mitochondria
and chloroplasts.
25. (c)
Chrysophytes belong to the kingdom protista.
Examples are diatoms and golden algae. Their
walls are embedded with silica and thus the walls
are indestructible.
26. (c)
Dinoflagellates are mostly marine and
photosynthetic organism. They appear yellow,
green, brown, blue or red depending on the main
pigments present in their cells. Most of them have
two flagella; one lies longitudinally and the other
transversely in a furrow between the cell plates.
27. (b)
Viroids cause potato spindle tuber disease
(PSTV), chrysanthemum stunt, citrus exocortis,
cucumber pale fruit etc. They cause persistent
infections, i.e., never recovered.
28. (d)
Kingdom animalia includes all heterotrophic,
multicellular complex eukaryotes. They depend
either upon plants or on other animals for their
food requirements. Kingdom monera includes
prokaryotic organisms lacking membrane bound
nucleus. Hence, nuclear membrane cannot be
found in Monera. Protista is a eukaryotic kingdom.
29. (b)
Chrysophytes are plant-like protists that can be
found in marine and freshwater environments
which are often low in calcium. There are three
main types of chrysophytes: diatoms
(bacillariophyta), golden-brown algae
(chrysophyceae), and yellow-green algae
(xanthophyceae).
30. (b)
Phycomycetes is a large and important class of
parasitic or saprophytic fungi, the algal or alga like
fungi. The plant body ranges from an undifferentiated
mass of protoplasm to a well developed and much-
branched mycelium. Mycelium is aseptate and
coenocytic. Asexual reproduction takes place by
spores and sexual reproduction by the formation of
conidia or sporangia.
31. (a)
Plasma membrane of eubacteria resembles
plasma membrane of eukaryotic cell. But nucleus,
ribosomes and cell wall are little different in
eukaryotic cell in their structure and organization
from eubacterial cell.
32. (a)
There are two major groups of monerans
archaebacteria (ancient bacteria) and eubacteria
(true bacteria). Eubacteria is of further two types
– bacteria and cyanobacteria. Thermoacidophiles
are a type of archaebacteria which live in extremely
acidic environment (pH 2) that have extremely
high temperatures (upto 110°C). They are found
in hot sulphur springs. Some of the eubacteria
are also famous for living under the most hostile
environment like salt pans, petroleum pans, spilled
oil, hot springs, sulphur springs, snow, etc.
33. (d)
Chemosynthetic autotrophic bacteria oxidise various
inorganic substances such as nitrates, nitrites and
ammonia and use the released energy for their ATP
production. They play a great role in recycling
nutrients like nitrogen, phosphorus, iron and sulphur.
34. (d)
Both plantae and aminalia are eukaryote.
35. (a)
In addition to the nucleoid, bacterial cytoplasm
normally contains many small, separate pieces of
DNA, called plasmids. These circular DNA units
are 1/100 the size of the main nuclear DNA
(nucleoid) and are also not enclosed in a membrane
structure. When found in cytoplasm, entirely
independent of the bacterial chromosome, they
replicate autonomously. Sometimes it becomes
integrated into the main DNA and replicates with it.
During conjugation, the plasmids, sometimes called
episomes, help in the transfer of the genetic material
between different bacteria. It may carry some
genes of resistance to a variety of antibiotics.
36. (d)
Infoldings of plasma membrane in bacteria are
called mesosomes.
37. (d)
Archaebacteria are believed to have originated at a
time when there were extreme conditions in the
biosphere. Even today they are found in environments
where other kinds of bacteria cannot survive. So they
are considered to be the oldest of the living fossils,
e.g., Methanobacterium, Methanococcus, etc.
All of them are not halophiles. Only some forms like
Halobacterium, Halococcus can survive under
extreme saline conditions. All of them are not fossils
because many forms are still surviving and flourishing.
38. (a)
Using Gram stain, developed by Danish physician,
Christian Gram in 1884, two kinds of bacteria were
noted - those species of bacteria that are decolorized
by alcohol are called Gram negative and those that
retain the stain are called Gram positive. This
property of bacteria is related with the structure
and compositional differences between the walls
of gram positive and gram negative forms. In the
cell wall of Gram positive bacteria, both horizontal
and vertical peptide linkages are present, due to
which mesh is dense and hence the stain does not
come out. Further outer layer of cell wall of Gram
positive bacteria is made of teichoic acid. In the
cell wall of Gram negative bacteria, either horizontal
or vertical peptide linkage are present, due to which
mesh is loose and hence stain comes out. Further
outermost layer of cell wall of Gram negative
bacteria is made of lipopolysaccharides.
39. (d)
Nucleoid is essential bacterial genetic material.
40. (c)
Heterotrophic bacteria are most abundant in
nature. The majority are important decomposers.
Many of them have a significant impact on human
affairs.
41. (b)
Mad cow disease in cattle is caused by prions.
Prions are disease causing agents having
abnormally folded proteins.
42. (d)
Infective constituent in the viruses is the genetic
material, i.e., either DNA or RNA.
Page 4
Solution
1. (a)
Protista include all unicellular and colonial
eukaryotes except those of green and red algae.
The protistan cells are typically eukaryotic having
membrane bound organelles like mitochondria,
chloroplasts, Golgi bodies, endoplasmic
reticulum, nucleus, etc. Protista is commonly
known as kingdom of unicellular eukaryotes.
Kingdom Fungi contains achlorophyllous, spore
producing, heterotrophic, multicellular or
multinucleate eukaryotic organisms (unicellular
yeasts are also included amongst fungi because
their sexual reproduction is similar to that of
some fungi). Monerans are basically unicellular
prokaryotes. Archaea (ancient bacteria) are also
a type of monerans which live in primitive
environment like high temperature, high salt
content, acidic pH, etc.
2. (b)
Streptococcus is a bacteria which is included
under Kingdom Monera. Monerans have
prokaryotic cell organisation in which membrane
bound organelles like mitochondria, E.R., Golgi
bodies, etc., are absent. All the other three i.e.,
Saccharomyces (a fungus), Chlamydomonas (an
algae) and Plasmodium (a protozoan protist) are
eukaryotes containing true membrane bound
organelles.
3. (b)
Association between roots of higher plants, e.g.,
pine, birch and fungal hyphae is called
mycorrhiza. It exhibits the phenomenon of
symbiosis. Here both the organisms in association
are mutually benefitted. In this, fungal hyphae
take nutrition from the plant and in return increase
surface area for absorption of water and minerals
for the plant.
4. (c)
Pseudopodia is the locomotory organ in amoeboid
protozoans, e.g., Amoeba. Flagellated protozoans
possess flagella for locomotion, e.g., Trypanosoma.
In sporozoans, locomotory organelles (cilia, flagella,
pseudopodia, etc.) are absent, e.g., Plasmodium.
Ciliated protozoans possess cilia as locomotory
organelles, e.g., Paramecium.
5. (a)
Both statements are correct.
6. (d)
Penicillium and Agaricus are fungi while Volvox
is an alga. All three are eukaryotes thus have a
membrane bound nucleus. Nostoc is a
cyanobacterium, i.e., prokaryote, so it lacks true
nucleus, thus nuclear membrane is absent.
7. (b)
The true fungi or the eumycetes are special types
of achlorophyllous thallophytic organisms living a
parasitic or a saprophytic mode of existence; they
are always heterophytes and never autophytes. They
depend on others for food, but all other groups as
algae, bryophytes and pteridophytes are chlorophyll
containing green plants that are autotrophic.
8. (b)
Kingdom Monera consists of prokaryotic
organisms, characterised by absence of nuclear
envelope around nucleus and absence of
membrane-bound cell organelles.
9. (b)
Gorgonia (sea-fan) is an animal belonging to
Phylum Coelenterata. All animals lack cell wall.
10. (b)
Viroids are free RNA particles that lack protein
coat. They are infectious agents smaller than
viruses.
11. (b)
All prokaryotic organisms come under Kingdom
Monera. Escherichia coli is a bacterium. Monera
includes bacteria, mycoplasmas, cyanobacteria (blue
green algae) and actinomycetes.
12. (b)
Diatoms are the most common form of
phytoplankton in the ocean. They have the
pigment chlorophyll which helps in photosynthesis.
Since, they are the primary producers of the
aquatic food chain and the marine ecosystem
depends on them. They are called chief producers
in the oceans.
13. (b)
Bacteria reproduce mainly by fission. Sometimes,
under unfavourable conditions, they produce
spores. They also reproduce by a sort of sexual
reproduction by adopting a primitive type of DNA
transfer from one bacterium to the other.
14. (a)
Diatoms are marine or freshwater unicellular
organisms which have cell walls composed of
pectin impregnated with silica and consisting of
two halves, one overlapping the other. The
siliceous frustules of diatoms do not decay easily.
15. (d)
Protista is a kingdom of unicellular eukaryotic
organisms. It includes photosynthetic protists
(dinoflagellates, chrysophytes and euglenoids),
consumer-decomposer protists (slime moulds) and
protozoan protists.
16. (c)
Chrysophytes include diatoms and desmids. The
body of diatoms is covered by a transparent siliceous
shell (silica deposited in cell wall) known as frustule.
The frustule is made of two valves, epitheca and
hypotheca, which fit together like a soap box.
17. (b)
Escherichia coli (bacterium) is not an example
of eukaryotic cell. It is a typical example of
prokaryotic cell.
18. (b)
NCERT figure 2.1
19. (b)
Blue green algae (cyanobacteria) are members
of kingdom monera.
20. (a)
Saprophytes are organisms that derive their
nutrition from dead or decaying organic matter.
Rhizopus, Aspergillus and mushrooms are some
of the examples of saprophytes.
In parasitism, only one species benefits (parasite)
and the interaction is harmful to the other species
(host). e.g: human liver fluke, malarial parasites
such as P. vivax, P. falciparum, etc.
Lichens is the mutualistic relationship between a
fungus and cyanobacteria. Similarly, mycorrhizae
is the symbiotic association between fungi and
the roots of higher plants.
21. (b)
Archaebacteria are found in most harsh habitats. Their
cell wall is adapted to tolerate extreme conditions
(wall contains protein and non-cellulosic
polysaccharides). Cell membranes are characterized
by the presence of branched chain lipids that make
them highly resistent to heat and low pH.
22. (c)
Methanogens are archaebacteria that live in
marshy area produce methane as a metabolic
byproduct in anoxic conditions. Methane is not
their preferred carbon source.
23. (b)
The sexual cycle involves the following three steps:
(i) Fusion of protoplasms between two motile or
non-motile gametes called plasmogamy.
(ii) Fusion of two nuclei called karyogamy.
(iii) Meiosis in zygote resulting in haploid spores.
24. (d)
Bacteria are microscopic organisms placed under
kingdom monera whose single cells have neither
a membrane-enclosed nucleus nor other
membrane enclosed organelles like mitochondria
and chloroplasts.
25. (c)
Chrysophytes belong to the kingdom protista.
Examples are diatoms and golden algae. Their
walls are embedded with silica and thus the walls
are indestructible.
26. (c)
Dinoflagellates are mostly marine and
photosynthetic organism. They appear yellow,
green, brown, blue or red depending on the main
pigments present in their cells. Most of them have
two flagella; one lies longitudinally and the other
transversely in a furrow between the cell plates.
27. (b)
Viroids cause potato spindle tuber disease
(PSTV), chrysanthemum stunt, citrus exocortis,
cucumber pale fruit etc. They cause persistent
infections, i.e., never recovered.
28. (d)
Kingdom animalia includes all heterotrophic,
multicellular complex eukaryotes. They depend
either upon plants or on other animals for their
food requirements. Kingdom monera includes
prokaryotic organisms lacking membrane bound
nucleus. Hence, nuclear membrane cannot be
found in Monera. Protista is a eukaryotic kingdom.
29. (b)
Chrysophytes are plant-like protists that can be
found in marine and freshwater environments
which are often low in calcium. There are three
main types of chrysophytes: diatoms
(bacillariophyta), golden-brown algae
(chrysophyceae), and yellow-green algae
(xanthophyceae).
30. (b)
Phycomycetes is a large and important class of
parasitic or saprophytic fungi, the algal or alga like
fungi. The plant body ranges from an undifferentiated
mass of protoplasm to a well developed and much-
branched mycelium. Mycelium is aseptate and
coenocytic. Asexual reproduction takes place by
spores and sexual reproduction by the formation of
conidia or sporangia.
31. (a)
Plasma membrane of eubacteria resembles
plasma membrane of eukaryotic cell. But nucleus,
ribosomes and cell wall are little different in
eukaryotic cell in their structure and organization
from eubacterial cell.
32. (a)
There are two major groups of monerans
archaebacteria (ancient bacteria) and eubacteria
(true bacteria). Eubacteria is of further two types
– bacteria and cyanobacteria. Thermoacidophiles
are a type of archaebacteria which live in extremely
acidic environment (pH 2) that have extremely
high temperatures (upto 110°C). They are found
in hot sulphur springs. Some of the eubacteria
are also famous for living under the most hostile
environment like salt pans, petroleum pans, spilled
oil, hot springs, sulphur springs, snow, etc.
33. (d)
Chemosynthetic autotrophic bacteria oxidise various
inorganic substances such as nitrates, nitrites and
ammonia and use the released energy for their ATP
production. They play a great role in recycling
nutrients like nitrogen, phosphorus, iron and sulphur.
34. (d)
Both plantae and aminalia are eukaryote.
35. (a)
In addition to the nucleoid, bacterial cytoplasm
normally contains many small, separate pieces of
DNA, called plasmids. These circular DNA units
are 1/100 the size of the main nuclear DNA
(nucleoid) and are also not enclosed in a membrane
structure. When found in cytoplasm, entirely
independent of the bacterial chromosome, they
replicate autonomously. Sometimes it becomes
integrated into the main DNA and replicates with it.
During conjugation, the plasmids, sometimes called
episomes, help in the transfer of the genetic material
between different bacteria. It may carry some
genes of resistance to a variety of antibiotics.
36. (d)
Infoldings of plasma membrane in bacteria are
called mesosomes.
37. (d)
Archaebacteria are believed to have originated at a
time when there were extreme conditions in the
biosphere. Even today they are found in environments
where other kinds of bacteria cannot survive. So they
are considered to be the oldest of the living fossils,
e.g., Methanobacterium, Methanococcus, etc.
All of them are not halophiles. Only some forms like
Halobacterium, Halococcus can survive under
extreme saline conditions. All of them are not fossils
because many forms are still surviving and flourishing.
38. (a)
Using Gram stain, developed by Danish physician,
Christian Gram in 1884, two kinds of bacteria were
noted - those species of bacteria that are decolorized
by alcohol are called Gram negative and those that
retain the stain are called Gram positive. This
property of bacteria is related with the structure
and compositional differences between the walls
of gram positive and gram negative forms. In the
cell wall of Gram positive bacteria, both horizontal
and vertical peptide linkages are present, due to
which mesh is dense and hence the stain does not
come out. Further outer layer of cell wall of Gram
positive bacteria is made of teichoic acid. In the
cell wall of Gram negative bacteria, either horizontal
or vertical peptide linkage are present, due to which
mesh is loose and hence stain comes out. Further
outermost layer of cell wall of Gram negative
bacteria is made of lipopolysaccharides.
39. (d)
Nucleoid is essential bacterial genetic material.
40. (c)
Heterotrophic bacteria are most abundant in
nature. The majority are important decomposers.
Many of them have a significant impact on human
affairs.
41. (b)
Mad cow disease in cattle is caused by prions.
Prions are disease causing agents having
abnormally folded proteins.
42. (d)
Infective constituent in the viruses is the genetic
material, i.e., either DNA or RNA.
43. (c)
(iii) The algal component is known as phycobiont
(iv) Fungal component as mycobiont.
44. (b)
RNA of viroid has low molecular weight.
45. (c)
Viroids are infectious RNA particles which were
discovered by T.O. Diener (1971). These are
devoid of protein coat and cause diseases in
plants only, e.g., potato spindle tuber,
chrysanthemum stunt, etc.
46. (b)
Slime moulds are saprophytic protists. The body
moves along decaying twigs and leaves engulfing
organic material. Under suitable conditions, they
form an aggregation called plasmodium which
may grow and spread over several feet.
47. (a)
Viruses can have either RNA or DNA as their
genetic material, however, they never have both
together. The entire infectious virus particle, called
a virion, consists of the nucleic acid and an outer
shell of protein.
Viruses are considered neither prokaryotes nor
eukaryotes because they lack the characteristics
of living things, except the ability to replicate
(which they accomplish only in living cells).
Chromosomes are present only in eukaryotic
organisms.
48. (b)
In viruses, three architectural forms are found –
helical (elongated body, e.g., TMV), cuboidal
(short broad body with rhombic, rounded,
polyhedral shape, e.g,. poliovirus) and binal (with
both cuboidal and helical parts, e.g., T
2
phage).
49. (c)
Yeast is a group of unicellular fungi of the class
ascomycetes. They occur as single cell or as a
group or chain of cells. Yeast of the genus
Saccharomyces ferments sugar and are used to
make bread and beer.
50. (a)
The nucleic acid of a virus is surrounded by a
protein coat called the capsid. The capsid is
composed of protein subunits called capsomeres.
In some viruses, the capsid is covered by an
envelope, which usually consists of some
combination of lipids, proteins and carbohydrates.
51. (b)
The kingdom of fungi consists of the eukaryotes,
heterotrophic organisms that show great diversity
in external features and habitat.
The fungi body except for unicellular yeast are
produced by long, slender, filamentous thread-like
structures known as hyphae.
A group of hyphae is known as mycelium.
52. (d)
Assertion : Agaricus (mushroom) and Ustilago
(smut) are members of basidiomycetes.
Reason : The mycelium is branched and septate.
The asexual spores are generally not found, but
vegetative reproduction by fragmentation is
common.
53. (d)
R.H. Whittaker considered complexity of cell
structure and structural (body) organisation, mode
of nutrition, ecological life style and phylogenetic
relationships for the five kingdom system of
classification.
54. (c)
Compared to many other group, monerans
(bacteria) show the most extensive metabolic
diversity. Some of the bacteria are autotrophic,
i.e., they synthesize their own food from inorganic
substrates. They may be photosynthetic
autotrophic or chemosynthetic autotrophic. The
vast majority of bacteria are heterotrophs, i.e.,
they do not synthesize their own food but depend
on other organisms or on dead organic matter for
food.
55. (a)
In order to develop phylogenetic classification,
R.H. Whittaker (1969), an American taxonomist,
divided all the organisms into five kingdoms.
Whittaker has used five criteria for delimiting the
different kingdoms.
(i) Complexity of cell structure, prokaryotic and
eukaryotic (ii) Complexity of body structure or
structural organization, unicellular and
multicellular. (iii) Mode of nutrition which is
divergent in multicellular kingdoms. (iv) Ecological
life style like producers (plantae), decomposers
(fungi) and consumers (animalia), (v)
Phylogenetic relationship. When such
characteristics were considered, the fungi were
placed in a separate kingdom – Kingdom Fungi.
All prokaryotic organisms were grouped together
Page 5
Solution
1. (a)
Protista include all unicellular and colonial
eukaryotes except those of green and red algae.
The protistan cells are typically eukaryotic having
membrane bound organelles like mitochondria,
chloroplasts, Golgi bodies, endoplasmic
reticulum, nucleus, etc. Protista is commonly
known as kingdom of unicellular eukaryotes.
Kingdom Fungi contains achlorophyllous, spore
producing, heterotrophic, multicellular or
multinucleate eukaryotic organisms (unicellular
yeasts are also included amongst fungi because
their sexual reproduction is similar to that of
some fungi). Monerans are basically unicellular
prokaryotes. Archaea (ancient bacteria) are also
a type of monerans which live in primitive
environment like high temperature, high salt
content, acidic pH, etc.
2. (b)
Streptococcus is a bacteria which is included
under Kingdom Monera. Monerans have
prokaryotic cell organisation in which membrane
bound organelles like mitochondria, E.R., Golgi
bodies, etc., are absent. All the other three i.e.,
Saccharomyces (a fungus), Chlamydomonas (an
algae) and Plasmodium (a protozoan protist) are
eukaryotes containing true membrane bound
organelles.
3. (b)
Association between roots of higher plants, e.g.,
pine, birch and fungal hyphae is called
mycorrhiza. It exhibits the phenomenon of
symbiosis. Here both the organisms in association
are mutually benefitted. In this, fungal hyphae
take nutrition from the plant and in return increase
surface area for absorption of water and minerals
for the plant.
4. (c)
Pseudopodia is the locomotory organ in amoeboid
protozoans, e.g., Amoeba. Flagellated protozoans
possess flagella for locomotion, e.g., Trypanosoma.
In sporozoans, locomotory organelles (cilia, flagella,
pseudopodia, etc.) are absent, e.g., Plasmodium.
Ciliated protozoans possess cilia as locomotory
organelles, e.g., Paramecium.
5. (a)
Both statements are correct.
6. (d)
Penicillium and Agaricus are fungi while Volvox
is an alga. All three are eukaryotes thus have a
membrane bound nucleus. Nostoc is a
cyanobacterium, i.e., prokaryote, so it lacks true
nucleus, thus nuclear membrane is absent.
7. (b)
The true fungi or the eumycetes are special types
of achlorophyllous thallophytic organisms living a
parasitic or a saprophytic mode of existence; they
are always heterophytes and never autophytes. They
depend on others for food, but all other groups as
algae, bryophytes and pteridophytes are chlorophyll
containing green plants that are autotrophic.
8. (b)
Kingdom Monera consists of prokaryotic
organisms, characterised by absence of nuclear
envelope around nucleus and absence of
membrane-bound cell organelles.
9. (b)
Gorgonia (sea-fan) is an animal belonging to
Phylum Coelenterata. All animals lack cell wall.
10. (b)
Viroids are free RNA particles that lack protein
coat. They are infectious agents smaller than
viruses.
11. (b)
All prokaryotic organisms come under Kingdom
Monera. Escherichia coli is a bacterium. Monera
includes bacteria, mycoplasmas, cyanobacteria (blue
green algae) and actinomycetes.
12. (b)
Diatoms are the most common form of
phytoplankton in the ocean. They have the
pigment chlorophyll which helps in photosynthesis.
Since, they are the primary producers of the
aquatic food chain and the marine ecosystem
depends on them. They are called chief producers
in the oceans.
13. (b)
Bacteria reproduce mainly by fission. Sometimes,
under unfavourable conditions, they produce
spores. They also reproduce by a sort of sexual
reproduction by adopting a primitive type of DNA
transfer from one bacterium to the other.
14. (a)
Diatoms are marine or freshwater unicellular
organisms which have cell walls composed of
pectin impregnated with silica and consisting of
two halves, one overlapping the other. The
siliceous frustules of diatoms do not decay easily.
15. (d)
Protista is a kingdom of unicellular eukaryotic
organisms. It includes photosynthetic protists
(dinoflagellates, chrysophytes and euglenoids),
consumer-decomposer protists (slime moulds) and
protozoan protists.
16. (c)
Chrysophytes include diatoms and desmids. The
body of diatoms is covered by a transparent siliceous
shell (silica deposited in cell wall) known as frustule.
The frustule is made of two valves, epitheca and
hypotheca, which fit together like a soap box.
17. (b)
Escherichia coli (bacterium) is not an example
of eukaryotic cell. It is a typical example of
prokaryotic cell.
18. (b)
NCERT figure 2.1
19. (b)
Blue green algae (cyanobacteria) are members
of kingdom monera.
20. (a)
Saprophytes are organisms that derive their
nutrition from dead or decaying organic matter.
Rhizopus, Aspergillus and mushrooms are some
of the examples of saprophytes.
In parasitism, only one species benefits (parasite)
and the interaction is harmful to the other species
(host). e.g: human liver fluke, malarial parasites
such as P. vivax, P. falciparum, etc.
Lichens is the mutualistic relationship between a
fungus and cyanobacteria. Similarly, mycorrhizae
is the symbiotic association between fungi and
the roots of higher plants.
21. (b)
Archaebacteria are found in most harsh habitats. Their
cell wall is adapted to tolerate extreme conditions
(wall contains protein and non-cellulosic
polysaccharides). Cell membranes are characterized
by the presence of branched chain lipids that make
them highly resistent to heat and low pH.
22. (c)
Methanogens are archaebacteria that live in
marshy area produce methane as a metabolic
byproduct in anoxic conditions. Methane is not
their preferred carbon source.
23. (b)
The sexual cycle involves the following three steps:
(i) Fusion of protoplasms between two motile or
non-motile gametes called plasmogamy.
(ii) Fusion of two nuclei called karyogamy.
(iii) Meiosis in zygote resulting in haploid spores.
24. (d)
Bacteria are microscopic organisms placed under
kingdom monera whose single cells have neither
a membrane-enclosed nucleus nor other
membrane enclosed organelles like mitochondria
and chloroplasts.
25. (c)
Chrysophytes belong to the kingdom protista.
Examples are diatoms and golden algae. Their
walls are embedded with silica and thus the walls
are indestructible.
26. (c)
Dinoflagellates are mostly marine and
photosynthetic organism. They appear yellow,
green, brown, blue or red depending on the main
pigments present in their cells. Most of them have
two flagella; one lies longitudinally and the other
transversely in a furrow between the cell plates.
27. (b)
Viroids cause potato spindle tuber disease
(PSTV), chrysanthemum stunt, citrus exocortis,
cucumber pale fruit etc. They cause persistent
infections, i.e., never recovered.
28. (d)
Kingdom animalia includes all heterotrophic,
multicellular complex eukaryotes. They depend
either upon plants or on other animals for their
food requirements. Kingdom monera includes
prokaryotic organisms lacking membrane bound
nucleus. Hence, nuclear membrane cannot be
found in Monera. Protista is a eukaryotic kingdom.
29. (b)
Chrysophytes are plant-like protists that can be
found in marine and freshwater environments
which are often low in calcium. There are three
main types of chrysophytes: diatoms
(bacillariophyta), golden-brown algae
(chrysophyceae), and yellow-green algae
(xanthophyceae).
30. (b)
Phycomycetes is a large and important class of
parasitic or saprophytic fungi, the algal or alga like
fungi. The plant body ranges from an undifferentiated
mass of protoplasm to a well developed and much-
branched mycelium. Mycelium is aseptate and
coenocytic. Asexual reproduction takes place by
spores and sexual reproduction by the formation of
conidia or sporangia.
31. (a)
Plasma membrane of eubacteria resembles
plasma membrane of eukaryotic cell. But nucleus,
ribosomes and cell wall are little different in
eukaryotic cell in their structure and organization
from eubacterial cell.
32. (a)
There are two major groups of monerans
archaebacteria (ancient bacteria) and eubacteria
(true bacteria). Eubacteria is of further two types
– bacteria and cyanobacteria. Thermoacidophiles
are a type of archaebacteria which live in extremely
acidic environment (pH 2) that have extremely
high temperatures (upto 110°C). They are found
in hot sulphur springs. Some of the eubacteria
are also famous for living under the most hostile
environment like salt pans, petroleum pans, spilled
oil, hot springs, sulphur springs, snow, etc.
33. (d)
Chemosynthetic autotrophic bacteria oxidise various
inorganic substances such as nitrates, nitrites and
ammonia and use the released energy for their ATP
production. They play a great role in recycling
nutrients like nitrogen, phosphorus, iron and sulphur.
34. (d)
Both plantae and aminalia are eukaryote.
35. (a)
In addition to the nucleoid, bacterial cytoplasm
normally contains many small, separate pieces of
DNA, called plasmids. These circular DNA units
are 1/100 the size of the main nuclear DNA
(nucleoid) and are also not enclosed in a membrane
structure. When found in cytoplasm, entirely
independent of the bacterial chromosome, they
replicate autonomously. Sometimes it becomes
integrated into the main DNA and replicates with it.
During conjugation, the plasmids, sometimes called
episomes, help in the transfer of the genetic material
between different bacteria. It may carry some
genes of resistance to a variety of antibiotics.
36. (d)
Infoldings of plasma membrane in bacteria are
called mesosomes.
37. (d)
Archaebacteria are believed to have originated at a
time when there were extreme conditions in the
biosphere. Even today they are found in environments
where other kinds of bacteria cannot survive. So they
are considered to be the oldest of the living fossils,
e.g., Methanobacterium, Methanococcus, etc.
All of them are not halophiles. Only some forms like
Halobacterium, Halococcus can survive under
extreme saline conditions. All of them are not fossils
because many forms are still surviving and flourishing.
38. (a)
Using Gram stain, developed by Danish physician,
Christian Gram in 1884, two kinds of bacteria were
noted - those species of bacteria that are decolorized
by alcohol are called Gram negative and those that
retain the stain are called Gram positive. This
property of bacteria is related with the structure
and compositional differences between the walls
of gram positive and gram negative forms. In the
cell wall of Gram positive bacteria, both horizontal
and vertical peptide linkages are present, due to
which mesh is dense and hence the stain does not
come out. Further outer layer of cell wall of Gram
positive bacteria is made of teichoic acid. In the
cell wall of Gram negative bacteria, either horizontal
or vertical peptide linkage are present, due to which
mesh is loose and hence stain comes out. Further
outermost layer of cell wall of Gram negative
bacteria is made of lipopolysaccharides.
39. (d)
Nucleoid is essential bacterial genetic material.
40. (c)
Heterotrophic bacteria are most abundant in
nature. The majority are important decomposers.
Many of them have a significant impact on human
affairs.
41. (b)
Mad cow disease in cattle is caused by prions.
Prions are disease causing agents having
abnormally folded proteins.
42. (d)
Infective constituent in the viruses is the genetic
material, i.e., either DNA or RNA.
43. (c)
(iii) The algal component is known as phycobiont
(iv) Fungal component as mycobiont.
44. (b)
RNA of viroid has low molecular weight.
45. (c)
Viroids are infectious RNA particles which were
discovered by T.O. Diener (1971). These are
devoid of protein coat and cause diseases in
plants only, e.g., potato spindle tuber,
chrysanthemum stunt, etc.
46. (b)
Slime moulds are saprophytic protists. The body
moves along decaying twigs and leaves engulfing
organic material. Under suitable conditions, they
form an aggregation called plasmodium which
may grow and spread over several feet.
47. (a)
Viruses can have either RNA or DNA as their
genetic material, however, they never have both
together. The entire infectious virus particle, called
a virion, consists of the nucleic acid and an outer
shell of protein.
Viruses are considered neither prokaryotes nor
eukaryotes because they lack the characteristics
of living things, except the ability to replicate
(which they accomplish only in living cells).
Chromosomes are present only in eukaryotic
organisms.
48. (b)
In viruses, three architectural forms are found –
helical (elongated body, e.g., TMV), cuboidal
(short broad body with rhombic, rounded,
polyhedral shape, e.g,. poliovirus) and binal (with
both cuboidal and helical parts, e.g., T
2
phage).
49. (c)
Yeast is a group of unicellular fungi of the class
ascomycetes. They occur as single cell or as a
group or chain of cells. Yeast of the genus
Saccharomyces ferments sugar and are used to
make bread and beer.
50. (a)
The nucleic acid of a virus is surrounded by a
protein coat called the capsid. The capsid is
composed of protein subunits called capsomeres.
In some viruses, the capsid is covered by an
envelope, which usually consists of some
combination of lipids, proteins and carbohydrates.
51. (b)
The kingdom of fungi consists of the eukaryotes,
heterotrophic organisms that show great diversity
in external features and habitat.
The fungi body except for unicellular yeast are
produced by long, slender, filamentous thread-like
structures known as hyphae.
A group of hyphae is known as mycelium.
52. (d)
Assertion : Agaricus (mushroom) and Ustilago
(smut) are members of basidiomycetes.
Reason : The mycelium is branched and septate.
The asexual spores are generally not found, but
vegetative reproduction by fragmentation is
common.
53. (d)
R.H. Whittaker considered complexity of cell
structure and structural (body) organisation, mode
of nutrition, ecological life style and phylogenetic
relationships for the five kingdom system of
classification.
54. (c)
Compared to many other group, monerans
(bacteria) show the most extensive metabolic
diversity. Some of the bacteria are autotrophic,
i.e., they synthesize their own food from inorganic
substrates. They may be photosynthetic
autotrophic or chemosynthetic autotrophic. The
vast majority of bacteria are heterotrophs, i.e.,
they do not synthesize their own food but depend
on other organisms or on dead organic matter for
food.
55. (a)
In order to develop phylogenetic classification,
R.H. Whittaker (1969), an American taxonomist,
divided all the organisms into five kingdoms.
Whittaker has used five criteria for delimiting the
different kingdoms.
(i) Complexity of cell structure, prokaryotic and
eukaryotic (ii) Complexity of body structure or
structural organization, unicellular and
multicellular. (iii) Mode of nutrition which is
divergent in multicellular kingdoms. (iv) Ecological
life style like producers (plantae), decomposers
(fungi) and consumers (animalia), (v)
Phylogenetic relationship. When such
characteristics were considered, the fungi were
placed in a separate kingdom – Kingdom Fungi.
All prokaryotic organisms were grouped together
under Kingdom Monera and the unicellular
eukaryotic organisms were placed in Kingdom
Protista. Kingdom Protista has brought together
Chlamydomonas, Chlorella (earlier placed in
Algae within Plants and both having cell walls)
with Paramecium and Amoeba (which were
earlier placed in the animal kingdom which lack
cell wall). It has put together organisms which, in
earlier classifications, were placed in different
kingdoms. This happened because the criteria for
classification has changed.
56. (d)
The Kingdom Monera includes all prokaryotes.
They are basically unicellular. The archaea and
nitrogen fixing organisms are placed under
monera. All others fungi, plantae, protists and
animalia are eukaryotic.
57. (a)
Kingdom monera include all prokaryotes.
58. (a)
Protists are single cell eukaryotes.
59. (b)
The prokaryotes are the primitive form of
organisms which do not have the membrane-
bound organelles. There do not have a well-
developed nucleus and other developed cellular
structures. Blue-green algae is commonly known
as the Cyanobacteria. These are prokaryotic
organisms and so, placed in this group.
60. (c)
Protista, fungi, plantae and aninalia are eukaryotes.
61. (a)
Halophiles can be found in salty areas where salt
concentration is very high.
A thermoacidophile is an extremophilic
microorganism that is both thermophilic and
acidophilic i.e., it can live under conditions of high
temperature and low pH.
Methanogens are microorganisms that produce
methane as a metabolic byproduct in hypoxic
conditions. It is found in guts of ruminants.
Cyanobacteria are a group of photosynthetic
bacteria, some of which are nitrogen-fixing, that
live in a wide variety of moist soils and water
either freely or in a symbiotic relationship with
plants or lichen-forming fungi. They can also be
found in aquatic environments.
62. (d)
Halophiles, a type of archaebacteria, usually occur
in extreme saline conditions like salt pans, salt
beds and salt marshes.
63. (b)
Methanogens are found in digestive tracts of
ruminants.
64. (c)
In Agaricus, (member of Basidiomycetes),
basidium commonly produces four meiospores or
basidiospores exogenously. Neurospora (member
of Ascomycetes) produces ascospores,
endogenously inside the fruiting body, ascus.
Alternaria (member of Deuteromycetes) does
not produce any sexual spores. Saccharomyces
(member of Ascomycetes) produces ascospores
endogenously.
65. (b)
Cell wall in fungi is composed of chitin, a
polysaccharide comprising N-acetyl-D-
glucosamine (a derivative of glucose).
66. (a)
Eubacteria are also called true bacteria.
67. (c)
Fungal cell wall contains chitin or fungal cellulose
along with other polysaccharides, proteins, lipids
and a number of other substances.
68. (c)
Deuteromycetes are the imperfect fungi which
include all those fungi in which sexual stage is either
absent or not known. Some members are saprophytes
or parasites while a large number of them are
decomposers of litter and help in mineral cycling. E.g.,
Colletotrichum, Helminthosporium, etc.
69. (a)
Morels are Ascomycetes with edible ascocarps
that have fleshy sponge-like conical cap or pileus
and a stalk like stipe, e.g., Morchella esculenta.
Truffles are also edible members of Ascomycetes
with tuber-like subterranean ascocarps that are
often dug out with the help of trained dogs and
pigs, e.g., Tuber aestivum.
70. (d)
Alternaria is a Deuteromycetes member which
are also known as fungi imperfecti. Their perfect
stages (sexually reproducing stages) are either
absent or not known.
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