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Biology (NCERT) - Class XI > XI Chap 2 Biological Classification > Flashcards

XI Chap 2 Biological Classification Flashcards

1
Q

___________ was the earliest to attempt a more scientific basis for classification using simple morphological characteristics

A

Aristotle

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2
Q

How did Aristotle divide animals into 2 groups?

A

Those that had red blood and those that didn’t

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3
Q

___________ developed the Two Kingdom system of classification

A

Linnaeus

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4
Q

What were the shortcomings of the Two Kingdom system?

A

did not differentiate between:

  • eukaryotes & prokaryotes
  • unicellular and multicellular
  • photosynthetic (green algae) and non-photosynthetic (fungi)
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5
Q

In the year ___________, ___________ proposed the Five Kingdom Classification

A

1969, R. H. Whittaker

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6
Q

What were the main classification criteria used by Whittaker?

A
  • cell structure
  • body organisation
  • mode of nutrition
  • reproduction
  • phylogenetic relationships
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7
Q

Monera is the only Kingdom that contains prokaryotic organisms, the remaining four are all eukaryotes. T or F?

A

True

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8
Q

Describe the cell wall of each of the Five Kingdoms

A 
Monera - Non-cellulosic (polysaccharide + amino acid)
Protista - Present in some
Fungi - Present, chitin
Plantae - Present, cellulose
Animalia - Absent
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9
Q

Nuclear membrane is present in all Kingdoms except Protista. T or F?

A

False, all except MONERA

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10
Q

Body organisation of Monera and Protista are cellular. T or F?

A

True

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11
Q

Describe body organisation of Fungi, Plantae and Animalia

A

Fungi - multicellular / loose tissue
Plantae - tissue / organ
Animalia - tissue / organ / organ system

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12
Q

Monera, Protista and Plantae have autotrophic organisms. T or F?

A

True

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13
Q

Name the five kingdoms

A 
Monera
Protista
Fungi
Plantae
Animalia
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14
Q

Earlier bacteria, blue green algae, fungi, mosses and ferns were classified under Plants. T or F?

What was the character that united this kingdom?

A

True

All organisms had a cell wall

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15
Q

Chlamydomonas and Spirogyra were earlier placed together under ____________

A

Algae

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16
Q

Fungi walls are made of ____________ whereas plant walls are made of ____________

A

chitin, cellulose

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17
Q

____________ are the sole members of Kingdom Monera

A

Bacteria

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18
Q

Bacteria are the most abundant micro-organisms. T or F?

A

True

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19
Q

Many bacteria live as parasites. T or F?

A

True

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20
Q

Autotrophic bacteria are the most abundant in nature. Majority of bacteria are important decomposers.

T or F?

A

False, HETEROTROPHIC are most abundant, rest is correct.

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21
Q

What are the 4 shapes of bacteria?

A
  1. Coccus / cocci- spherical
  2. Bacillus / bacilli - rod-shaped
  3. Vibrium / vibrio - comma-shaped
  4. Spirillum / spirilla - spiral
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22
Q

Though the bacterial ____________ is very simple, they are very complex in ____________

A

structure, behavior

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23
Q

Bacteria as a group show the most extensive ____________ diversity

A

metabolic

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24
Q

Some bacteria are autotrophic. They synthesize their food from organic substrates. T or F?

A

False,

first sentence is correct, INORGANIC substrates

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25
Q

Autotrophic bacteria are of two types:

A

Photosynthetic

Chemosynthetic

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26
Q

____________ bacteria are the oldest-living

A

Archaebacteria

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27
Q

____________ bacteria live in the most harsh habitats

A

Archaebacteria

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28
Q

Where do the following archaebacteria live?

Halophiles, thermoacidophiles and methanogens

A

Halophiles - extremely salty areas
Thermoacidophiles - hot springs
Methanogens - marshy areas

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29
Q

Methanogens are present in the ____________ of ruminant animals like cows and buffaloes. They are responsible for the production of ____________ from ____________ of these animals

A

gut, methane (biogas), dung

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30
Q

There are thousands of different ____________ (kind of bacteria)

A

eubacteria

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31
Q

Eubacteria is aka ____________

A

true bacteria

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32
Q

Eubacteria are characterised by a ____________ cell wall and ____________ if motile

A

rigid, flagellum

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33
Q

Cyanobacteria aka ____________ have ____________ pigment similar to green plants

A

blue-green algae, chlorophyll a

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34
Q

Cyanobacteria are:
multicellular/unicellular?
colonial/filamentous/both?
freshwater/marine/terrestrial/some combination?

A

unicellular,
colonial or filamentous,
freshwater, marine and terrestrial

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35
Q

Cyanobacteria colonies are surrounded by ____________

A

gelatinous / mucilagenous sheath

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36
Q

Cyanobacteria form ____________ in polluted water bodies

A

blooms

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37
Q

What are heterocysts?

A

Specialized cells in cyanobacteria in which atmospheric nitrogen is fixed

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38
Q

Chemosynthetic autotrophic bacteria ____________ various inorganic substances such as ____________, ____________ and ____________ and use the released energy for their ATP production.

A

oxidise,

nitrates, nitrites and ammonia

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39
Q

____________ (kind of bacteria) play a great role in recycling nutrients like nitrogen, phosphorus, sulphur and iron.

A

Chemosynthetic autotrophic bacteria

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40
Q

Bacteria that make curd from milk, involved in the production of antibiotics and that fix nitrogen in legume roots are all heterotrophic. T or F?

A

True

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41
Q

What are 4 diseases caused by bacteria?

A

Cholera, typhoid, tetanus, citrus canker

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42
Q

Bacteria reproduce mainly by ____________

A

fission

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43
Q

Under unfavorable conditions for reproduction, bacteria ____________

A

produce spores

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44
Q

Bacteria reproduce sexually as well using ____________ type of ____________ transfer

A

primitive, DNA

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45
Q

____________ are smallest living cells known

A

Mycoplasma

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46
Q

Mycoplasma have a cell wall and can survive without oxygen. T or F?

A

False, do NOT have a cell wall, rest is correct

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47
Q

Many mycoplasma are pathogenic in plants and animals. T or F?

A

True

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48
Q

All single-celled eukaryotes are placed under the kingdom ____________

A

Protista

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49
Q

Boundaries of ____________ kingdom are not well-defined.

A

Protista

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50
Q

What are the groups of organisms in Protista?

A
  1. Chrysophytes
  2. Dinoflagellates
  3. Euglenoids
  4. Slime Moulds
  5. Protozoans
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51
Q

Members of Protista are primarily ____________ (aquatic / terrestrial)

A

aquatic

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52
Q

Protistan cell body contains a well-defined nucleus and other membrane-bound organelles. T or F?

A

True

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53
Q

Protists produce asexually as well as sexually by process involving ____________ and ____________

A

cell fusion, zygote formation

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54
Q

Some protists have flagella and cilia. T or F?

A

True

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55
Q

Chrysophytes are:

  • mostly photosynthetic / heterotrophic / holozoic?
  • fresh water / marine / either?
  • visible to the naked eye / microscopic?
A

mostly photosynthetic
freshwater as well as marine
microscopic

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56
Q

Chrysophytes float passively in water currents like ____________

A

plankton

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57
Q

Diatoms and Desmids belong to the group ____________

A

Chrysophytes

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58
Q

Desmids are aka ____________

A

golden algae

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59
Q

Describe diatoms’ cell walls

A

2 thin overlapping shells, fit together like a soap box

Walls embedded with silica => indestructible

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60
Q

Diatomaceous earth?

A

Large amount of cell wall deposits in habitats of diatoms, accumulated over billions of years

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61
Q

Diatoms are also referred to as the __________ in the oceans

A

chief producers

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62
Q

Diatomaceous earth is used in __________, __________ of oils and syrups

A

polishing, filtration

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63
Q

Dinoflagellates:

  • mostly photosynthetic / heterotrophic / holozoic?
  • fresh water / marine / either?
  • colors?
A

mostly photosynthetic,
mostly marine,
red, yellow, green, blue and brown

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64
Q

Describe cell walls of dinoflagellates

A

Stiff cellulose plates on outer surface

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65
Q

Do dinoflagellates have flagella?

A

Yes, 2. One longitudinal, one transversely in a furrow between wall plates.

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66
Q

Red dinoflagellates for example ___________ undergo such rapid multiplication that they make the sea appear red and release ________

A

Gonyaulax, toxins that kill other marine animals

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67
Q

Euglenoids are:

  • mostly photosynthetic / heterotrophic / holozoic?
  • fresh water / marine / either?
A

photosynthetic in sunlight, otherwise heterotrophic

mostly fresh water (STAGNANT water)

68
Q

Describe cell wall of euglenoids

A

No cell wall,

protein rich layer called PELLICLE => makes their body flexible

69
Q

Do euglenoids have flagells?

A

Yes, 2, one long and one short

70
Q

Pigments of ________ are identical to higher plants

A

euglenoids

71
Q

Example of Euglenoid?

72
Q

Slime moulds are:

- mostly photosynthetic / heterotrophic / holozoic?

A

Saprophytes

73
Q

Slime moulds move along decaying twigs and leaves engulfing ____________

A

organic material

74
Q

Under suitable conditions, slime moulds form _____________

In unfavourable conditions, they ___________

A

form an aggregation called plasmodium, several feet.

plasmodium differentiates, forms fruiting bodies which bear spores at their tips

75
Q

Spores produced by slime moulds possess _______ walls, are extremely resistant and are dispersed by _______

A

true walls, air currents

76
Q

All protozoans are _______

A

heterotrophs

77
Q

All protozoans live as predators or parasites. T or F?

78
Q

_______ are believed to be primitive relatives of animals

A

Protozoans

79
Q

What are the 4 major groups of protozoans?

A
  1. Amoeboid protozoans
  2. Flagellated protozoans
  3. Ciliated protozoans
  4. Sporozoans
80
Q

Ameboid protozoans live in _______, _______ or _______

A

fresh water, sea water or moist soil

81
Q

Ameboid protozoans move and capture their prey by putting out _______

A

pseudopodia (false feet)

82
Q

Marine forms of ameboid protozoans have _______ shells on their surface

83
Q

Some ameboid protozoans like _______ are parasites

84
Q

Flagellated protozoans are either free-living or _______

85
Q

Parasitic forms of flagellated protozoans cause diseases like _______

A

sleeping sickness

86
Q

Trypanosoma is a _______ whereas Paramoecium is a _______

A

flagellated protozoan, ciliated protozoan

87
Q

Ciliated protozoans are _______ (aquatic / terrestrial) and are actively moving because of the presence of thousands of _______

A

aquatic, cilia

88
Q

Ciliated protozoans have a cavity that opens to _______

A

the outside of the cell surface

89
Q

Coordinated movement of cilia in ciliated protozoans causes _______ laded with food to be steered into the _______

A

water, gullet

90
Q

Sporozoans are diverse organisms that have a _______ stage

A

infectious spore-like

91
Q

Example of sporozoan?

A

Plasmodium (malarial parasite)

92
Q

_______ constitute a unique kingdom of heterotrophic organisms

93
Q

White spots seen on mustard leaves are due to _________

A

a parasitic fungus, Albugo

94
Q

_________ fungus causes rust in wheat

95
Q

_________ and _________ are cosmopolitan

A

Fungi, bacteria

96
Q

_________ fungus is a source of antibiotics

A

Penicillium

97
Q

Fungi prefer to grow in _________ and _________ places

A

warm, humid

98
Q

With the exception of _________ which are unicellular, fungi are filamentous.

99
Q

What are hyphae and mycelium?

A

Hyphae - Long, slender thread-like structures

Mycelium - network of hyphae

100
Q

What are coenocytic hyphae?

A

Continuous tubes filled with multinucleated cytoplasm

101
Q

Non-coenocytic hyphae have _________ or _________ in the hyphae

A

septae, cross walls

102
Q

Cell walls of fungi are composed of chitin and _________

A

polysaccharides

103
Q

Most fungi are _________, while some are _________ and can also live as _________

(mode of nutrition)

A

saprophytes, parasites, symbionts

104
Q

Examples of symbionts are fungi in association with _________ as lichens and with _________ as mycorrhiza

A

algae, roots of higher plants

105
Q

Reproduction in fungi can take place by vegetative measures _________, _________ and _________

A

fragmentation, fission and budding

106
Q

Asexual reproduction in fungi takes place by spores called _________ or _________ or _________ and sexual reproduction takes place by _________, _________ and _________

A

asexual - conidia, sporangiospores, zoospores (CSZ)

sexual - oospores, ascospores, basidiospores (OAB)

107
Q

Spores of fungi are produced in distinct structures called _________

A

fruiting bodies

108
Q

Sexual cycle in fungi involves 3 steps. They are?

A
  1. Plasmogamy (fusion of protoplasms between 2 motile or non-motile gametes)
  2. Karyogamy (fusion of 2 nuclei)
  3. Meiosis (zygote -> haploid spores)
109
Q

In some fungi, the fusion of two haploid cells immediately results in diploid cells (2n). T or F?

110
Q

What is dikaryon / dikaryophase of fungus?

A

In some fungi - ascomycetes and basidiomycetes - an intervening dikaryotic stage occurs where there are 2 nuclei per cell

111
Q

What are the classes of the Fungi kingdom? What is the basis of their division?

A

Phycomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes

On the basis of: morphology of mycelium, mode of spore formation and fruiting bodies

112
Q

Members of phycomycetes are found in _________ (terrestrial / aquatic) habitats and on _________ in moist and damp places or as ________ on plants

A

aquatic,
decaying wood,
obligate parasites

113
Q

Describe mycelium of Phycomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes

A

Phycomycetes - aseptate and coenocytic
Asco - branched and septate
Basidio - branched and septate
Deutero - branched and septate

114
Q

Describe asexual reproduction of Phycomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes

A

Phyco - zoospores (motile) or aplanospores (non-motile), endogenously produced in sporangium
Asco - conidia produced exogenously on conidiophores (special mycelium)
Basidio - asexual reproduction not found, vegetative reproduction by fragmentation
Deutero - conidia

115
Q

Describe sexual reproduction of Phycomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes

A

Phyco - zygospore formed, isogamous or anisogamous or oogamous
Asco - ascospores, endogenously produced in sac-like asci
Basidio - sex organs absent, but plasmogamy happens by fusion of 2 vegetative or somatic cells => dikaryotic structure => basidium => 4 basidiospores exogenously produced on basidium
Deutero - not found

116
Q 
Classify into the various fungi classes.
Penicillium
Mucor
Aspergillus
Agaricus
Saccharomyces
Trichoderma
Claviceps
Alternaria
Ustilago
Rhizopus
Puccinia
Colletotrichum
Neurospora
Albugo
A 
Penicillium - Asco
Mucor - Phyco
Aspergillus - Asco
Agaricus - Basidio
Saccharomyces - Asco
Trichoderma - Deutero
Claviceps - Asco
Alternaria - Deutero
Ustilago - Basidio
Rhizopus - Phyco
Puccinia - Basidio
Colletotrichum - Deutero
Neurospora - Asco
Albugo - Phyco
117
Q

Match the following:

  • Bread mould
  • Smut causing fungus
  • Biochemical and genetic work
  • Mushroom
  • Parasitic fungi on mustard
  • Making bread and beer
  • Rust causing fungus (wheat)
  • Edible delicacies

Puccinia, morels, Ustilago, Trichoderma, Agaricus, Penicillium, Saccharomyces, truffles Rhizopus, Albugo, Neurospora

A 
Bread mould - Rhizopus
Smut causing fungus - Ustilago
Biochemical and genetic work - Neurospora
Mushroom - Agaricus
Parasitic fungi on mustard - Albugo
Making bread and beer - Saccharomyces 
Rust causing fungus on wheat - Puccinia
Edible delicacies - morels and truffles
118
Q

Ascomycetes are commonly known as __________ and are mostly __________ (unicellular / multicellular)

A

sac-fungi, multicellular

119
Q

Yeast is among the rare unicellular members of ascomycetes. T or F?

120
Q

Ascomycetes are saprophytic, decomposers, parasitic or __________ (growing on dung)

A

coprophilous

121
Q

Conidia of ascomycetes on germination produces __________

122
Q

The sac-like asci that produce sexual spores in ascomycetes are arranged in different types of fruiting bodies called __________

123
Q

Morels and truffles (edible delicacies) belong to which class of Fungi?

A

Ascomycetes

124
Q

Commonly known forms of basidiomycetes are __________, __________ and __________

A

mushrooms, bracket fungi, puffballs

125
Q

Basidiomycetes grow in __________, on __________ and __________ and in plant bodies as __________

A

soil,
logs and tree stumps
parasites

126
Q

In plasmogamy in basidiomycetes, the fusion of two vegetative or somatic cells is of __________ (similar / different) strains or genotypes.

127
Q

The basidia in basidiomycetes are arranged in fruiting bodies called __________

A

basidiocarps

128
Q

__________ class of fungi is commonly known as imperfect fungi because __________

A

Deuteromycetes,

because only the asexual vegetative phases of these fungi are known

129
Q

Most deuteromycetes are __________ (decomposers or saprophytes)

A

decomposers,

litter and mineral recycling

130
Q

Some members of deuteromycetes are saprophytes or parasites. T or F?

131
Q

Kingdom __________ includes all eukaryotic chlorophyll-containing organisms.

132
Q

Few members of plant kingdom are partially heterotrophic, such as __________ plants or __________

A

insectivorous, parasites

133
Q

Specify whether these plants are insectivorous or parasitic:
Bladderwort
Cuscuta
Venus fly trap

A

Bladderwort - insectivorous
Cuscuta - parasite
Venus fly trap - insectivorous

134
Q

Plantae includes algae. T or F?

135
Q

What is alternation of generation?

A

2 distinct phases in life cycle of plants - diploid sporophytic and haploid gametophytic - that alternate with each other

136
Q

Kingdom __________ includes heterotrophic eukaryotic organisms that are multicellular and their cells lack cell walls.

137
Q

Animals digest their food in an internal cavity and store food reserves as __________ or __________

A

glycogen, fat

138
Q

Mode of nutrition of animals is __________ i.e. ingestion of food

139
Q

Higher forms of animals show elaborate __________ and __________ mechanism

A

sensory, neuromotor

140
Q

All animals are capable of locomotion. T or F?

A

False, MOST are

141
Q

Sexual reproduction in animals is by __________ of male and female followed by __________

A

copulation, embryonic development

142
Q

Viruses did not find a place in classification since they are __________

A

not considered truly living

143
Q

Viruses are __________ organisms (cellular / non-cellular) characterized by having a __________ crystalline structure outside the __________

A

non-cellular, inert, living cell

144
Q

Virus means __________ or __________

A

venom, poisonous fluid

145
Q

__________ (in the year______) recognized certain microbes as causal organisms of the mosaic disease of tobacco.

A

Dmitri Ivanowsky (1892)

146
Q

Microbes discovered by D. Ivanowsky were found to be __________ (smaller / larger) than bacteria because they __________ (passed through / were caught by) bacteria-proof filters

A

smaller, passed through

147
Q

In the year ____, __________ demonstrated that the extract of infected plants of tobacco could cause infection and named the new pathogen __________ and the fluid as ________ ________ ________

A

1898, MW Beijerinek, virus, Contagium vivum fluidum (infectious living fluid)

148
Q

In the year ____, __________ showed that viruses could be crystallised and crystals consist largely of __________

A

1935, W. M. Stanley, proteins

149
Q

Viruses are obligate parasites as they are inert outside their host cell. T or F?

150
Q

Viruses contain RNA, DNA or both. T or F?

A

False, never contain BOTH

151
Q

A virus is a ________-protein and the genetic material is infectious.

A

nucleoprotein

152
Q

Identify genetic material of these types of viruses:

  1. infect plants
  2. infect animals
  3. infect bacteria
A
  1. infect plants - SS RNA
  2. infect animals - SS RNA, DS RNA, DS DNA
  3. infect bacteria - DS DNA
153
Q

Protein coat of virus is called ________

154
Q

Capsid is made of small subunits called ________ and protects the ________

A

capsomeres, nucleic acid

155
Q

Capsomeres are arranged in ________ or ________ forms

A

helical, polyhedral geometric forms

156
Q

Name 5 diseases caused by virus

A

AIDS, herpes, mumps, small pox, influenza

157
Q

What are the symptoms of virus diseases in plants?

A
  • mosaic formation
  • leaf rolling and curling
  • yellowing and vein clearing
  • dwarfing
  • stunted growth
158
Q

In ____, ________ discovered viroid, a new infections agent that was smaller than viruses and caused ________ disease.

A

1971, T. O. Diener, potato spindle tuber disease

159
Q

Viroids are free RNA => they lack the protein coat. T or F?

160
Q

RNA of viroid is of ________ (higher / lower) molecular weight than that of viruses.

161
Q

What are prions?

A

Abnormally folded protein,

transmits certain infectious neurological diseases

162
Q

Size of prions compared to viruses?

A

Similar size

163
Q

What is the most notable disease caused by prions? What are all its names?

A

Bovine spongiform encephalopathy (BSE)
In cattle - mad cow disease
In humans - Cr-Jacob disease (CJD)

164
Q

________ are symbiotic associations between algae and fungi

165
Q

The algal component of a lichen is called ________ and is ________ (autotropic/heterotrophic).
The fungal component is called ________ and is ________ (autotropic/heterotrophic).

A

phycobiont, autotrophic

mycobiont, heterotrophic

166
Q

Lichens are good pollution indicators as they ___________

A

do not grow in polluted areas

Biology (NCERT) - Class XI (23 decks)

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