PK Ncert Flashcards
Earliest system of classification used
gross superficial morphological
characters
gross superficial morphological
characters in early system of classification had features like
habit, colour, number and shape of leaves
Artificial system if classification were mainly based on
Vegetative characters
Linnaues gave artificial system based on _____ structure
Androecium
Problem with artificial systems
- Separated closely related species
- Gave equal weightage to floral and vegetative characters (which are affected by environment)
natural classification systems were based on
natural affinities among the organisms
factors considered by natural system
internal features, like:
- ultrastructure
- anatomy
- embryology
- phytochemistry
George benthom and Joseph Dalton Hooker gave ___ classification for _____ plants
Natural system, flowering
phylogenetic classification systems based on
evolutionary relationships- orgs in same taxa have common ancestor
Many resources were being used mainly after
Supporting fossil evidences werent found
Numerical taxonomy
carried out using computers is based on all observable
characteristics
each character is given equal
importance and at the same time hundreds of characters can be
considered by
Numerical taxonomy- Number and codes are assigned to all the characters and
the data are then processed
Cytotaxonomy is based on
chromosome number, structure, behaviour
chemical constituents of the plant is used for
chemotaxonomy
Algae habitat
Largely aquatic
Moist stones, soil, wood
All algae have chlorophyll. T/F
True
Algae are found in association with
fungi- lichens
sloth bear
colonial
forms
like Volvox
filamentous forms like
Ulothrix and Spirogyra
A few of the marine forms such as
kelps, form massive plant
bodies.
These gametes can be
flagellated and similar in size in
(as in Ulothrix)
or non-flagellated (non-motile)
but similar in size
(as in Spirogyra).
Rep in spirogyra and ulothrix are
isogamous
Fusion of two gametes dissimilar in size, as in species of
——- is termed as anisogamous.
Eudorina
Fusion between one ——- female gamete and a —— male gamete is termed
oogamous, e.g., Volvox, Fucus.
large, nonmotile (static)
smaller, motile
At least a — of the total
——– fixation on earth is carried out by algae through
——-.
half, CO2, photosynthesis
Being —— Algae increase the level of ——-
oxygen in their immediate environment.
photosynthetic, dissolved
They are of paramount
importance as —–producers of ——rich compounds which form
the basis of the food cycles of all —– animals.
primary
energy
aquatic
Many species of —–, —- and —– are among the — species of marine algae
used as food
Porphyra,
Laminaria and Sargassum
70
Certain —– brown and red algae produce large amounts
of —— e.g., algin (brown algae) and
—– (red algae) which are used commercially
-marine
-hydrocolloids (water holding substances),
-carrageen
Agar, one of the
commercial products obtained from —– and —- are used to
grow —– and in preparations of —— and —–.
Gelidium and Gracilaria
microbes
ice-creams and jellies
Chlorella a
—— alga rich in —– is used as food supplement even by —–
unicellular
proteins
space travellers
plant body of —– may be unicellular, colonial or filamentous
Chlorophyceae
grass green colour of green algae is due to the dominance of
pigments chlorophyll a and b
The
pigments of green algae are localised in definite chloroplasts. The chloroplasts may be —-, —-, —–, ——, —- in
different species
discoid, plate-like, reticulate, cup-shaped, spiral or ribbon-shaped
Most of the members of green algae have one or more storage bodies
called —– located in the —–.
pyrenoids, chloroplasts
Pyrenoids contain ——
besides starch. Some algae may store food in the form of —–
protein
oil droplets
Green algae- cell wall made of an inner layer of —–
and an outer layer of —–.
cellulose
pectose
Asexual reproduction is by
—— zoospores produced in
flagellated, zoosporangia
Commonly found green algae (5)
Chlamydomonas, Volvox, Ulothrix, Spirogyra and Chara
—– algae show great variation in size and form
Phaeophyceae
Phaeophyceae habitats
marine
They range
from simple branched, filamentous forms (——) to profusely
branched forms as —–,
Ectocarpus
kelps
kelps may reach a height of
100 metres
Pigments in brown algae
chlorophyll a, c, carotenoids and xanthophylls
Brown algae vary in colour from —– to various shades of —— depending
upon the amount of the —— pigment, ——- present in it
olive green, brown
xanthophyll
fucoxanthin
Food is stored as ——carbohydrates, which may be in the
form of —–.
complex
laminarin or mannitol
The vegetative cells of brown algae have a —— cell wall usually covered on the —-by a —– coating of algin
cellulosic
outside
gelatinous
Centrally located vacuole and nucleus is seen in
brown algae
The plant body of brown algae is usually attached to the —- by a
holdfast, and has a stalk, the —- and — like photosynthetic organ
the —-
substratum
stipe
leaf
frond
Asexual
reproduction in most brown algae is by ——zoospores that are
—– shaped and have two unequal —- attached flagella.
biflagellate
pear-shaped
laterally
Union of gametes in brown algae may take place in —- or ——
in water or within the oogonium
(oogamous species)
Gametes of brown algae are —- shaped
pear shaped- pyriform
Examples of brown- 5
Ectocarpous, Laminaria, Fucus, Dictyota, Sargassum
Red algae mainly have —- pigment
, r-phycoerythrin
Majority
of the red algae are —-with greater concentrations found in the —–
areas
marine, warmer
Red algae occur in both —– regions close to the —- of water
and also at great —- in oceans where relatively little light penetrates.
well-lighted, surface
depths
Some of red algae
have — body organisation
complex
Food stored in red is —-
which is very similar to —–and glycogen in —-.
floridean starch
amylopectin
structure
Sexual reproduction in red algae is by —- gametes
non motile
Complex post fertilization development is seen in
red algae
—– are found
commonly growing in moist shaded areas in the hills
Bryophytes
Bryophytes are also called —- of the plant kingdom because
these plants
amphibians
are dependent on water for sexual
reproduction.
bryo usually occur in —-localities.
damp, humid and shady
bryo play an important role in plant succession on
bare rocks/soil.
bryo plant body is thallus-like and ——, and attached to the substratum
by unicellular or multicellular —-.
prostrate or erect
rhizoids
—- lack true roots, stem or
leaves.
bryo
They may possess root-like, leaf-like or stem-like structures.
The main plant body of the bryophyte is —-.
haploid
The sex organs in bryophytes are —–.
multicellular
Antheridium of bryo produces ____
antherozoids. The female sex organ called archegonium is —–shaped
and produces a single egg.
biflagellate
flask
The antherozoid of bryo are released into —- where they come in contact with archegonium.
water
Zygotes of bryo do not undergo —– division
immediately. They produce a —- body called a — .
reduction
multicellular
sporophyte
The sporophyte is not free-living but attached to the —-
gametophyte and derives —- from it.
photosynthetic, nourishment
Bryophytes in general are of little —- importance but some
mosses provide — for —-mammals, birds and other animals.
economic
food
herbaceous
Mosses along with —- are the first
organisms to colonise — and hence, are of great —-importance.
lichens, rocks
ecological
Species of Sphagnum, provide —that have been used as —, and as packing material for—- of living material because
of their capacity to —–
peat, fuel
trans-shipment
hold water.
Moss —– rocks making the substrate suitable for the growth of
— plants.
decompose, higher
Since mosses form dense mats on the soil, they reduce the—- and prevent—- .
impact of falling rain
soil erosion
liverworts grow usually in habitats such as —
banks of
streams, marshy ground, damp soil, bark of trees and deep in the woods
The plant body of a liverwort is thalloid, e.g., —-.
Marchantia
The thallus is
— and closely appressed to the substrate.
dorsiventral
The leafy members of liverworts
have tiny leaf-like —-in —rows on the stem-like structures
appendages , two
Asexual reproduction in liverworts takes place by —— of
thalli, or by the formation of specialised structures called —
fragmentation
gemmae
Gemmae are ——, —–, —– buds, which
develop in small —-called gemma cups located on the thalli.
green, multicellular, asexual
receptacles
The gemmae become detached from the parent body and germinate to
form — new individuals.
2
The
sporophyte of liverworts is differentiated into —.
foot, seta and capsule.
The predominant stage of the life cycle of a moss is the —– which
consists of — stages.
gametophyte, 2
The first stage of gametophyte of moss is the — , which
develops directly from a —-.
It is a —-, —, —- and
frequently filamentous stage
protonema, spore
creeping, green, branched
The second stage is the —stage, which
develops from the —– as a lateral bud.
leafy, secondary protonema
The leafy stage of moss consist of
upright, — axes bearing ——- arranged leaves.
slender
spirally
Secondary protonema of moss are attached
to the soil through —- and branched rhizoids.
multicellular
—- stage of moss bears
the sex organs.
Leafy
Vegetative reproduction in mosses is by —- and —-
in the secondary protonema
fragmentation
budding
Sex organs are formed at ____ of leafy shoots in moss
apex
The sporophyte in —– is more elaborate than
that in —-.
moss more elaborate than liverwort
The — of moss contains spores.
capsule
The mosses have an elaborate mechanism of —-
spore dispersal.
Common examples of mosses are - 3
Funaria, Polytrichum and Sphagnum
Pteridophytes are used
for —- purposes and as —-. They are also frequently grown
as ——.
medicinal
soil-binders
ornamentals
Evolutionarily, —- are the first terrestrial plants to possess vascular tissues – xylem and phloem.
pterido
The pteridophytes are found in cool, damp,
shady places though some may flourish well in —–soil conditions.
sandy
In pteridophytes, the
main plant body is a —-which is differentiated into — root,
stem and leaves
sporophyte, true (These organs possess well-differentiated
vascular tissues)
The leaves in pteridophyta are small (microphylls) as
in —– or large (macrophylls) as in —-.
Selaginella
ferns
The sporophytes bear
—- that are subtended by leaf-like appendages called —–
sporangia , sporophylls
compact
structures of sporophytes in pterido called —- are seen in
strobili or cones
(Selaginella, Equisetum).
The spores of pterido
germinate to give rise to —, small but multicellular, free-living, mostly —-thalloid —- called prothallus.
inconspicuous, photosynthetic
gametophytes
The gametophytes of —require cool, damp, shady places to grow. Because of this specifc restricted requirement and the need for water for fertilisation, —-
pterido
the spread of living pteridophytes is limited and restricted to narrow geographical regions.
Water is required for transfer of —-– of pterido
antherozoids
Zygote of pterido produces a multicellular —— sporophyte
which is the —- phase of the pteridophytes.
well-differentiated
dominant
In majority of the
pteridophytes all the spores are of — kinds; such plants are called
—-.
similar, homosporous
Genera like —- and — which produce
two kinds of spores, macro (large) and micro (small) spores, are known
as —–.
Selaginella and Salvinia
heterosporous
The megaspores and microspores germinate and give
rise to —— and — gametophytes, respectively.
male and female
The pteridophytes are further classified into four classes: Psilopsida
(—-); —— (—-, Lycopodium), Sphenopsida (—–)
and Pteropsida (Dryopteris, —–, —–).
Psilotum
Lycopsida- selaginella
Equisetum
Pteris, Adiantum- walking fern
The female
gametophytes in heterosporous plants are —— sporophytes
for variable periods. The development of the zygotes into young —-
take place —-
retained on the parent
embryos
within the female gametophytes.
Dev of zygote in parent sporophyte is a —- to
the —- considered an important step in evolution.
precursor
seed habit
Gymnosperm means
(gymnos : naked, sperma : seeds)
i.e. ovules are not enclosed by any ovary wall and remain exposed, both
before and after fertilisation
The Gymnosperms include —-sized trees or tall trees and —
medium, shrubs
Tallest gymnosperms is
the giant
redwood tree Sequoia
The roots are
generally —- roots.
Roots in some genera have —- association in the
form of —- (Pinus), while in some others (Cycas) small specialised
roots called —- roots are associated with N2
- fixing ——.
tap (for xerophytic adaptations)
fungal- mycorrhiza
coralloid
cyanobacteria
The stems of gymno are unbranched (—–) or branched (—–).
Cycas
Pinus, Cedrus
The leaves of gymno
may be —– . In Cycas the —- leaves persist for a few
years.
simple or compound
pinnate
The leaves in gymnosperms are well-adapted to withstand extremes
of —–,—– and —.
temperature, humidity and wind
In —- , the needle-like leaves reduce the —-. Their thick —- and —–stomata also
help to reduce water loss.
conifers
surface area
cuticle, sunken
Gymnosperms are homosporous. T/F
False
The two kinds of
spores in gymno are produced within —- that are borne
on sporophylls which are arranged —- along an axis
to form —- or compact strobili or cones.
sporangia
spirally
lax
The microspores in gymno develop into a male gametophytic
generation which is highly reduced and is confined to only a limited number of cells called
Pollen grain
The development
of pollen grains take place within the ——.
microsporangia
The male or female cones or strobili may be
borne on the same tree (in —–).
Pinus- monoecious
In —- male
cones and megasporophylls are borne on different trees.
cycas, diecious
The megaspore mother cell of gymno female is differentiated from one of the cells of the —–.
nucellus
The nucellus is protected by —- and the composite structure is called—– .
envelopes, Ovule
The ovules are borne on —- in gymno which
may be clustered to form the female cones.
megasporophylls
One of the —– in gymno is enclosed within the
megasporangium and develops into a multicellular female
gametophyte that bears —- archegonia.
megaspores
two or more
in gymno, the male and the female gametophytes
—- independent free-living existence. They
remain within the sporangia retained on the
—–.
do not have
sporophyte
The pollen grain is released from the
microsporangium of gymno are carried in —–and come in contact with the opening of the —borne on megasporophylls.
air currents
ovules
The —- in gymno, carrying the male gametes grows towards archegonia in the ovules
and discharge their contents near the mouth of the archegonia.
pollen tube
In angiosperms
or —- plants, the pollen grains and ovules are developed in
specialised structures called —-.
the seeds are
enclosed in —–.
flowering
flowers
fruits
The angiosperms are an exceptionally large group of
plants occurring in —- of habitats.
wide range
smallest angio —- and tallest tree of —-.
Wolffia
Eucalyptus (over 100 metres)
angio provide
us with ——– and several other commercially
important products.
food, fodder, fuel, medicines
Depending on the type of —– possesed and the type of—-, algae are classfied into
three classes, namely Chlorophyceae, Phaeophyceae and Rhodophyceae.
pigmnet
stored food
Algae usually reproduce asexually by
formation of different types
spores
