Chapter two

Biological Classification
Classification of Systems of
Living Organisms Classification
Biological or scientific Living organisms are divided into following
• In the 18th century, a Swedish biologist
categories
classification in biology Carolus Linnaeus developed a scheme
• Carolus Linnaeus ( 1758) placed all the
is a method of scientific of scientific classification and devised a
living organisms in two major kingdoms,
system of scientific nomenclature.
taxonomy used in i.e. Plantae for plants and Animalia for
According to him, all organisms have
grouping or categorizing animals. This system is also known as
some important characteristics in
Two Kingdom System of classification . In
organisms into groups common and different from others in
this categorisation, the position of some
such as genus or species. one or more ways are placed in a
organisms like Eug/ena, blue-green
category termed as species, i.e. cat,
These groups are known monkey, housefly, frog, etc . algae, fungi, etc., was debatable.
as taxa. • Different species having certain • Ernst Haeckel placed all the organisms
common characters are placed in a into three groups, i.e. Protista, Plantae
genus. In the same manner different and Animalia . It is also known as Three
genus are placed in family. The order is Kingdom System of classification .
as under • Copeland (1956) divided the organisms
Species (Lowest level) ➔ Genus ➔ into four kingqoms, i.e. Monera (bacteria
Family ➔ Order ➔ Class ➔ Phylum ➔ and blue-green algae), Protista (red and
Kingdom (Highest level). brown algae, :fungi and Protozoa),
Plantae and Animalia. It is known as
Four Kingdom Systen1 of classification .
Binomial Nomenclature In it, the position uf fungi in Protista was
1
Proposed by Linnaeus in his book Species debatable.
PlantarUm. The scientific name of each First well accepted classification of
organism is composed of two names, i.e. a organisms was given by RH Whittaker
. generic name and a species name. The generic (1969) who classified the organisms into
name begins with a capital letter and five major kingdoms, i.e. Monera ,
species name begins with a small letter, i.e. Protista, Fungi, Plantae and Animalia on
Zoological name of the common housefly is the basis of cell structure, plant body
Musca domestica and that of human is organisation, nutrition mode, .
Homo sapiens. The botanical name of wheat reproduction and ancestral relationships.
is Triticum aestivum. It is called Five Kingdom System of
classification . This was the first kingdom
system classified the debatable organism
in proper place.
 118
Whittaker (1969)
proposed bY _-· - - -- ... -- ----------
Comparison of Five Kingdom - p1a_nta~ . ___ ----~~~~~"'--._,,
funo 1 Eukaryolic Eukaryotic '--.,
Features Monera Protlsta E: ukaryulic
Type of c-rll p l'Q ~ ,l l Ytll IL
(nul lru 5 ,.vi tlm111
r 11k11ryo tle
(1111clcus with
nuc!car n1e111 br
. ~~i.1 11el
. pr~;nt and
--- . -- ------
Absent ---.,
11 11 clt• ,w 1111'111lm 111rl - Pr; se~ ;nd made from
Cell 1\ ,1 !1 No11rr ll ulosic present Present In sorne made from chitin cellulose
,:ind 111ade from
µo ly~accharide (pol ymer
of glucose )
--·--··--·-- -·-
----·-· ___ _ _______Tissue/organ
----
Tissue/org~
-·----
_______ -·- - Multicellular vel organ system
lk gan i'.:>J111)n Cellular level but loose tissue _ I~ - - - - - - - - - '1/11
Ce llu lar level 1

P,resent --- "

01 l'(lti ) - -- Presen t
- - - -- - Present
Mctrbr ilne Absent and Present - - -- -- - -
,M}und nuc leus nu_cleo_i_d i· _
ss~
pr~e~se~n!._
t _ _ _ _ _~ - - - -1_~ili(;-;;i ·Autotrophic Autotr~~
- - Autotrophic~ mode present absent °01:
Tyl)€ 0f nu trition Autotropic mode present Autotrophic mode absent
(preparation mode present
of food by own) Heterotrophic Heterotrophic
Heterotrophic mode absent mode present
Heterotrophic mode Heterotrophic
mode present
prese nt (depend for food mode present
on others) Algae, moss, fern, All anima~
Example Plant, fungus and Various fungus
Bacteria gymnosperm and
animal like organism flowering plants

Six Kingdom System

-· · · · · · ·· · h b t ria and eubacteria. This system is based
Latest system of class1ficat1on 1s Six Kingdom System which d1v1des Monera into arc ae ac _e . db
on comparison of RNA (ribonucleic acid) a single-stranded genetic material present mostly in lower organisms propose Y
CWoose, 0 Kandler and MC Wheelis in (1990).

Kingdom-Monera
• Ki ngdom-Monera constitutes bacteria, archaebacteria,
mycoplasma , actinomycetes, cyanobacteria and rickettesia .
• Bacteria are major/main organisms of this kingdom. They
• /L.......,..,,..... Ribosomes
lack true nucleus and present in each and every habitat Cytoplasm
includ ing some extreme area like hot springs, snow and Nuclear area (nucleoid)
deep oceans. containing DNA
Bacteria are of two types
Archaebacteria These are primitive bacteria which mostly
inhabited in extreme habitats. Archaebacteria can be
categorised into three types, i.e . Methanogens (methane
producing bacteria) , e.g. Methanobacterium, etc .,
Halophiles (marine bacteria), e.g. Halobacterium and
Thermoacidophiles (sulphur bacteria) e.g. Su/fo/obus, etc.
Eubacteria These are true bacteria which have cellulosic cell
Eubacterial cell
wall. Their structure is shown in side-wise figure .
• Three basic shapes of eubacteria are Cocci (spherical), Bacillus (rod-shaped) and iril • . s
Presence of flagella is an important feature of bacteria Flagella are thread 1·k p hum (spiral and helical-shaped).
• • - 1 e structures m tf II r
arrangement on bacteria may be atrichous (without flagella, e.g. Lactobacillus) mono . ean . or movement. Flage a
e.g. Xa~th?monas), amphitrichous (one flagella at each ehd, e.g. Alka/igens) I~ h _tnchous (single flagella at one end,
e.g. Spmll1Um) and peritrichous (flagella on whole body, e.g. Proteus). ' P otnchous (group of flagella at one end,
 •~ , I

•: Magbook ~ Biological Classification

Mycoplasma (Joker ol Microbiology) 1898) .

• It was discovered by Nocafd and Roux (_
Plasmid (Extra DNA in Bacteria) II aerobic ,
These are smallest, lack ceII wa ' their shape)
I Plasmid is very important in biot echnology as it is use d as o vory ange
nun -motile, pleomorphic (ca n ch_ RNA and
. irnportant tool. Due to It's stnall , highly replicating 11a1u1u ii is usocl to
and proka ryotlc orga nism, contains bol h
transfer and cloning of the desired gone. Duo tu this 1111111ru ii is also
called cloning vector. DNA . These are also called PPLO, i.e.
pleuropneurnonla like org,misms.
Economic Importance of Bacteria
staining of Bacteria
• Bacteria causes number of diseases in plants,
• Christian Gram , a Danish bacteriologist in 19th century
animals, human, etc.
developt>d a rn eth0d to differentiate bacteria by colouring them .
o n the basis 01 colour adaptation he divided the bacteria into Human Diseases Caused by Bacteria
Grill11 Positi ve and Gram Negative bacteria .
-------
Diseases Pathogens
Comparison of Gram Positive and - Cholera Vibrio cholerae
-------- - . -·-· ·-
Gram Negative Bacteria E3act~ial dy;~tery Shiegella dysenteriae
--------- - - - - - - -- - - - -- - ----- -----
cri,ract~ iSlic _ Gram Positive Gram Negative Plague Yersinia pestis
Grani reac tion
- ---:-----:-:--- - - - --=-==-~.:____:_---
Achieve violet or pu rple Achieve red colour in Rh~ icfever Streptomyces sp .
colour in colouring colouring (staining)
Tuberculosis Mycobacterium tuberculosis
_____ - ~ aining) process. process.
Streptococcus pneumoniae

-----
Lipid, protein and
.: Jrbohyd rate content
- - - - ---
-rlarmful prod ucts
Ve ry low to low

Exotoxins (toxin act

High

Endotoxin (toxin act in

Pneumonia

Typhoid Salmonella typhi

Leptospiraictero haemorrhagiae
- - - _______
(toxi ns) outside the body)
__:___ _____ side the body)
__.:...___ Jaundice
Diphtheria Corynebacterium diphtheriae
1
Nutrition in Bacteria Escherichia coli
Gastroenteritis
, On the basis of their energy requirements and ability to
Syphilis Treponema pallidum
synthesise essential metabolites, the bacteria may be
autotrophic (self food producing) or heterotrophic (taking food Gonorrhoea Neisseria gonorrhoeae
from other) Bacterial conjunctivity Haemophilus influenzae
On the basis of behaviour of nutrition, heterotrophic bacteria are Clostridium tetani
Tetanus
divided into
- Saprophytic bacteria, (i.e. depends on dead organic matter) Diarrhoea Bacillus coli
- Symbiotic bacteria , (i .e. bacteria establish association with other
organisms) . Plant Diseases Caused by Bacteria
- Parasitic bacteria , (i .e. bacteria getting food from other organisms) . Diseases Pathogens
- - - - - - - - - -- - - - -- - - - - -
Reproduction in Bacteria Leaf spot of cherry Coccomyces hiemates
• Like other living organisms, bacteria also reproduce through Ring spot of potato Xanthomonas solanacearum
various methods.
Blight of walnut Xanthomonasjuglandes
• Asexual reproduction takes place in bacteria by vegatative
method and spore formation. The common means of vegetative Blight of paddy Xanthomonas oryzae
reproduction in bacteria is binary fission . Some bacteria multiply Bacterial spot of peach Xanthomonas prunii
by budding. Citrus canker Xanthomonas citri
• Lederberg and Tatum (1946) proved that sexual reproduction Xanthomonas malvacearum
Angular leaf spot of cotton
takes place in bacteria . There are three methods of sexual
Blight of bean Pseudomonas phaseolicola
reproduction in bacteria.
• Bacteria reproduce by Transformation, the process explained by Crown gall of sugarbeet Agrobacterium tumefaciens
F Griffith (1928) in which bacteria exchange their genetic Wilt of tobacco Phytobacterium solanacearum
material through conjugation tube. During conjugation, [given by Soft rot of mango Bacterium cartovorus
Lederberg and Tatum ( 1946)] bacteria exchange their genetic
Tundu of wheat Corynebacterium tritici
material through sex pili. For the process of transduction,
[explained by Zinder and Lederberg (1952)] the bacteria
• Bacteria are also very useful for obtaining good
exchange their genetic material through bacteriophages. products.
• c',) ' 1f I )'i"' •,, ·: /'11 ,\'1 ( , ... ,'N. l /11'1 1 111'/ I) l it)( lr11,1 ,Jl t' J S 1111r1N
Some Important lndu~trial and
other Products and their Sources
81.,ma Important Antibiotics
and their Sources Important Industrial Produch sources

Acetic ac id
Acetobuctc r orru
Sources
Ac;~n~ ;~d-bulanol (.'J ostridwm acetoh- •
Bocil, us bre\,i5 _ Ufy/;,
i r-•"' 11 t- i'C e-l'•n elc. Lactic acid
5tr'? !o~occus luq; '·
B. C'CTeus
~-'l \ 1,l(i n llc henifor~in, etc~ - Ace tobocler
8 lirh en iforrrns Synthetic rubber
ro1,m1 \ in- 8 ----- -- --- - - - Clostridium uretob
___ _ _ Uty/v
B. pol\ mv,a Vllamin -B
Bacil r ac in, eun1yc 1n, bacil lomycin, etc. Bacillus megateri~m ..
B. subtllls Fla~ouring of tea
Kanarnycin and tobacco
S-t,eptom y~eskanom ycelicus ------ - Various lacto·b~ci//1;~
Terrarnyci n Milkproducts --- .
S. rimosus Methanobacillus
( hloromycrctin -M~than~ ;~ -~ bi~gasl
S. venezueloe --~-

Klngdom-Protlsta ·
1
.
. They have we11 t animals and fungi
• Pro11~,a con1ains all eukaryotic single-celled organisms that resembles ~ 1th _Pans , re mostly marine and contains
d01in(lld nucleus and other membrane bound organelles . Members of this kingdom a
chry:,ophy1 es , dinoflagellates, euglenoids , slime moulds and protozoa.

Kingdom-Protista
I - - - - -~ - - - L - - . - - - - 7 - - - ~
Chrysophytes Dinoflagellates Euglenoid Slime Moulds or Protozoa or
0 1 Golden algae. or Protists with flagella Photqsynthetlc Protists Fungi like protists Animal like protists
e.g. Diatom (algal like) e.g Gonyaulax e.g. Euglena e.g. Fonticula e.g. Amoeba

Economic Importance of Protista

• Protistans cause several diseases in human being, a list of some disease with their general details are given
as under
Pathogenic Protozoans of Humans
Parasitt Habitat Disease and Distribution Mode of Transmission
Balonridiurn coli Large intestine Ciliary dysentery and World-wide. By taking cysts with food and drink.
En romorbo hisrolttiro Large intestine Amoebic dysentery and World-wide. By swallowing
- - - -- - - - - - - -------- ---- - - - - - - -- - - - - - - cysts with food and drink. ;
Giordia in resrinolis
Upper part of human Flagellate diarrhoea and World-wide. By taking cysts with food and waler.
small intestine
- -- - - -·:-::----- :- - --;-:- -:----- :-:-~- ------- -- - - - - - - - -
te,shmonio donovoni Cells of liver, spleen, l<ala-azar and India -- - 1
lymph glands and WBC s By bites of sandfly (Phlebotomus
argentipes l.
L IIOf'IC0 Endothelial cells of skin Cuteneous oriental sore, - - - --- -- - -1
cap illarie!> By bites of sandfly (Phlebotomus sergentil
Persia and Arabia
Ptosmod,um vivox liver eel Is Benign tertian malaria.
By bites of female Anopheles mosquito.
P. molo11oe -do- Quartan malaria and Tropical countries.
-do-
T(YJXJfl050111Q l nitial ly blood and later Gambian sleeping sickness and
gombiense cerebrospinal fluid Central Africa. By bites of tse-tse fly (G_ pulpiness).

T. rhodesitnse I nltlally blood and later Rhodes ian ~Jeeping slckne~s-.;d - - - - - - - - -- - -- - - ~

cerebrosplnal fluid South Eastern Af rl ca. By bites of tse-tse fly ( G. pa/polis and
_ __ G. morsitans).
T. cruzi BloodSouth Americ an trypanosomlasis (Cha _a_ _ _ _ - - - - - - - - - 01
di sease), Central and South America g s B~ cont~mination of wounds with faeces
- - - --- - · triatom1d bugs.
Trirhomonos vagina/is Vagina Leucorrhoea and World~ id e,
- - - -- - - - - - --- - - - - - - -
T. hominis Large intestine Mild diarrhoea and Wo~ rl~
d-:w~id~e~.-
By coitus (sexual intercourse) .
----- =~-=-=
By taking active trophozoit~;-dep~;lted r,
- - - - -- - - - - - - - -- - - - - -- - - - - - -~ f~oo~d~b~y~fl~ie:_s
·: __ i
 '-' ~•u , \.J ldti::i ll lL;(l(.1011 I I- o

1<1ngdom-Fungl
Fungi is a grn up 111 Un,n \ Plant Diseases Caused by ~ungi __ __ _____ _
_ - ,, 10. u1gl,111s 111 11,1v11 ,p 1:!!I I wo1II ol
C-I11lin Lrn c1 lw lPIutro ,)I11 - 11 . . ' Plant Dlse111e Fungus
1- l ' odv ol 11ulI ,110,1, Uody Is
11 ad e 11 ~~ 0 t 1t1 ,1m 1.:11t~ lll 1I <',1d I1I,c ) c,) lled Wa rl di se ase of polulo Synchytrium endob 1-?_,_ticum
r · hyphae which _ _
rorni ,1 11e h, 01 I, cJlkd n,yc"'II ' R _ ' Stem rot of papaya
_ " 1um _ eprodu ctlon takes Pythium uph~node;rn?__t~m- - ----
\"\JC€ by f1_ ag111cn t.il 1nn by .
._ I d - Late bligh,t o(polat o
, asexua an sexual spores . Phytophthom infesto n5_____ ___
ru11~1c1,c Lb::--~1t 1cL10 11 th e b - f
asIs o morpho logy of -Powdery mildew ofpeas - --- Erysiphe polygoni
111 \·celH1111 ,ind 111ode of spo f t·
i re orma 10n _ Powdery mildew of wheat - - - E ,ysi phe polygoni
Fungi Downy mildew of peas Peronos
, - 1 -__l_ _ White rust of crucifers
- - - -- ----poru --
pisi
PfWt,,--OO,yc,:1tes Albugo candida
, ,\ f,>Jf i \..ti tung,,
Ascomycete 5
or Sac 1
~
Basldiomycetes Deuteromycetes Green ear of bajra Sclerospora grominicolu
' , ;; 11-A--or and e g Neu ung,, or Mushrooms , or lmperlect fungi , - - - --:-- :---- - - -- - - ----· ---
· · ro spora Black rust of wheat
q,-- ~_x-,1>l'-, Albugo . Clavic ' . e.g _Agaricus . e.g. Alternaria and Puccina graminis tritici
ep s Ustilago and Puccinia , Trichode rma , Flag smut of wheat Urocystis tritici
Loose smut of wheat Ustilago tritici
Mushroom Covered smut of barley Usti/ago hordei
These_are used as foo_d du_e to their flavour, protein and Loose smut of barley Ustilago nuda
vi tamin contents _Their edible part is basidicarp (has fleshy Covered smut of barley Ustilago kolleri
stalk and ~~brella-shaped cap or pileus) _Agaricus Whip smut of sugarcane Ustilago scitamineae
campe_ stns 1~ common edible mushroom whereas, Amanita
Grain smut of jowar Sphacelotheca sorghii
phyffo,dos poisonous in nature.
Smut of bajra Tolyposorium penicillari
Economic Importance of Fungi Early blight of potato Alternaria solani
Fungi are benefi cia l as well as harmful. Tikka disease of ground nut Cercospora personata
Several diseases caused by fungi are explained as follows: Red rot of sugarcane Colletotrichum folcatum
Blast disease of rice Pyricufaria oryzae
Human Diseases Caused by Fungi
W i It of arhar Fusarium udum
Human Diseases Fungus Club root disease of crucifer s Plasmodiophora brassicae
Aspergillosis Aspergillus fla vus, A. fumigatus and A. niger Stem gall of coriand er
Protomyces macrosporus
Blastomycosis 8/astomyces dermatitidis Leaf rust of coffee
Haemelia vastarix
Candidiasis Candida albicans
Chromomycosis
• Fungi are also used as food for obtaining important products .
Cladosprium corrionii
Cocc idiomyc osis
- - - - - - - - -- Penicillium It is a fungi which includes number of species , few
Coccidiodes immitis
- - - - - -- - - - - species are saprophyte and few are parasites, e.g. Penicillium
Cryptoco cc osis Lipomyces neoformans notatum is known for the production of antibiotics.
Geotrichosis Geotrichum candidum Some commercially important products obtained from fungi and
Histoplasmosis Histoplasma capsula tum their resources are as under
~ -- - - - - - - - - - - - - - -
Neuriti s Mucor pusillus
Some other Important Products
Onychomyco sis Trichophyton purpureum and their Source Fungi
Sportot richosis Sportotrichum schenkii
Important Products Source Fungi
Mushro oms (edible fungi)
Some Animal Disease Caused by Fungi Various Agaricus sp.
Vitamin -B and D Yeast
Animal Diseases Fungus Colvaci n (Anti cancer drug) Calvatia
Athelet e foot Tineo rubrum
~ - - - -· ·- - Ethyl alcohol Yeast
Ringwo rm Trichophyton, Microsp orum Flavour ed cheese Penicillium
and Epidermophyton
Citric acid Aspergillus
__Mucom ycosis
___:__ - --
Asper gi 11 osis
Mucor and Rhizo~us _____ _
--:-- ~- Fumari c acid Rhizopus
Aspergilfus
Gibberel l ic acid (plant hormon e) Fusarium
Penicil losis Penicillium
Various enzymes Aspergillus
 122 Magbook ~ General Sci
en~

• Aflatoxins are naturally occuring mycotoxins, whlct1 are produced by Algae

many species of Aspergillus, fungus. Fungus can be considered as a Algae are mostly aquatic (freshwater and
type .of mo:ild • Aflatoxins are toxic and are among the most marine), autotrophic, chlorophyll bearing
carcmogenrc substances known . thalloid plants. They ranges from unice11ui fC
colonial to filamentous forms . Reproductit p
Symbiotic Association of Fungi
,-------~----
Lichens
Mycorrhlza
takes place by vegetative (fragmentation) n
asexual (flagellated zoospores) and sexu~1
(fusion of two gametes, isogamy, anisogan,y
(Alg8Q t lllngi)
(Fungi + roots of higher plants) and oogamy) means.
, Grow in humid and
uninhabited places Algae show rapid reproducti~n and make a
• Algae pro\~de food to fungi. Ectomycorrhlza Endomycorrhlza huge colony in the water. This massive growth
• Fungi anchors and absorbs (Fungi, on surface of root) (Fungi, inside root)
is called algal bloom . Algal bloom caused b
H,O and minerals from SO•. • Plant provides shelter and food to fungi.
• Are bioindicaters tor air · • Fungi helps plant in following ways : red algae is called red tide. Rapid growth Y
pollutants (sulphur dioxide) . Abosrbs H,O and minerals specially H, and P exhaust the nutrient from the environment and
• Ramalina and Evernia are from soil due to the presence of phase.
used to prepare dhup,
affect other organisms (Eutrophication). Alga
• Provides growth promoting and antimicrobia
cosmetic, soaps, etc. substances enables plant to tolerate extremes
are also very important for obtaining e
of pH . economically important substances.
Algae can be classified as
Klngdom-Plantae
Algae
• Kingdom-Plantae includes chlorophyll containing eukaryotic organisms. p
But some plants are insectivorous (insect eating plants, bladder wort
and venus fly trap) and parasite (Cuscuta) . Major characteristic of Chlorophyceae Phaeophyceae Rhodophyceae
plants is the presence of cell wall made up of cellulose. (green algae) (brown algae) (red algae)

• Plantae includes algae, bryophytes, pteridophytes, gymnosperms and Some important Algal member are as follows :
angiosperms. C Linnaeus (1758) divided these group of plants into
cryptogams (without visible sex organs and phanerogams (with visible Some Important Algae used as Food
sex organs). Engler divided the plants into Thallophyta (embryo stage Laminaria Nostoc and Durvillea
absent) and Embryophyta (Embryo stage present). A/aria Codium
Monostroma Chondrus
• Theophrastus is known as the Father of Botany. His famous book is
Undaria Spirulina
Historia P/antarum. Scenedesmus
Ulva
• Thallophyta Undifferentiated plant body that has no roots, stems or Ch/ore/la Porphyra, Graci/aria and Gelidium
leaves is called Thallophyta, (i.e. Cladophora).
Some other Economically Important
• Tracheophyta (also called vascular plants) Those plants that have
Products and their Source Algae
lignified tissues for conducting water and minerals throughout the
plant, (i.e. Fucus alba). Important Product Source Algae
0 2 production for Ch/ore/la and
Some Important Antibiotics and their Sources astronauts Synechococcus
Antibiotic Source Chlorellin (antibiotic) Ch/ore/la
Penicillin Penicillium notatum and P. chrysogenum Agar-agar (Jelly-like Gelidium and Graci/aria
Ergotine Claviceps purpurea (sclerotia); Given after childbirth material)
Griseofulvin Penicillium griseofulvum; in skin diseases (ringworm) Iodine Laminaria and Macrocystis
Biofertilisers
Citrinine
Campestrin
P. citrinum
Psaliotta campestris {Agaricus campestris}
Nostoc, Anabaena, etc.

Some algae also cause several diseases in plants

-
Baccatin-A Gibberella baccata and animals as Cephaleuros virescens causes red
Glyotoxin Trichoderma sp. rust of tea and Nostoc and other brown algae
- - - - - - - - -- - ----------·······----···--···---··- - - - - - cause death of aquatic animals.
Proliferin Aspergillus proliferans
Chaetomin Chaetomium cochloides
Bryophytes
Jawaharine Aspergillus niger • Commonly called as amphibians of plant
Fumigallin kingdom as they are found both in dry and
Aspergillus fumigatas niger
moist area . Mostly found in hilly area . Body
Clavicin Aspergillus clavatus have root-like, stem-like and leaf-like structure. :
Flavicin Aspergillus flavus and A. fumigatus no true organs. i
 ain plant body (gamete Prod . . 'd hytes separate
• Male and female gametes~ Fuci~.g 0 ~ gametophyte) ➔ archaegonia Unlike bryophytes, 1n pten op . .
· . f d Fertil1sat1on
Msporophytic body (spore :tih~ation (water required) free living gametophytic stage 1s not oun · z t
~ t seta and capsule) ~ Spro ucing body, divided into lakes place that leads to the formation of zygote . ~go e
~~~t body (gametophytic). pores ➔ Germination ➔ New lead to the formation of embryo. Ovules converted into
aryophytes are classified as under seeds that are not covered.
• Cycas It is a woody gymnosperm with natural seedS,
Bryophytes which bears male and female cones on separate plants.

Liverwortsd )
-~-- -
Hornworts
Mosses (Bryopsida)
• Mycorrhizae is a symbiotic association between a fungus
and the root of vascular plants.
(Hepaticops, a (Anthocer .
g. Riccia. Marchantia e g AnthopSida) e.g. Funaria
e· · · oceros Sphagnum' Angiosperms
• Angiosperms are flowering plants hence, flower is the
most important feature of this group of plants as it
Sphagnum contains/bears male (pollen grain) and female (embryo
5fl"n1,8gnum
·
is the chief constituents of peat h' h .
t· f , w 1c 1s used as sac) gametophyte in specialised structures called
tvel and in prepara ion o ethyl alcohol It h th . androecium and gynoecium respectively. Fruit is the
' · d h . · as e capacity to
I retain rno1stur~ _an t at is why used in transportati f another major character of angiosperms. These ranges
moisture requ1r1ng products. on ° from microscopic Wolfia to tall trees Eucalyptus.
• Angiosperms are recently evolved plants. Body is
Pteridophytes sporophytic and differentiated into true root, stem and
, pteridophytes are leaves. Plants are annual, biennial and perennial. Found
. . first terrestrial plants poss ess1ng
•
vascular tissue, i.e . xylem and phloem . Major habitats are in many habitats and some forms show hydrophic
cool, shady places but some ones are also found in sandy (present in water) nature, parasitic nature (Cuscuta) and
soil. Used as ornamental plants. epiphytic (present on other plant for food and shelter)
, Main plant body (spore producing or sporophyte) ➔ nature.
Spores ➔ Spore germinate ➔ Prothallus ➔ Bear male and , Angiosperms are divided into dicots and monocots based
female gametophyte ➔ Produces male and female on the presence of cotyledons (part of embryo) . Dicots
gametes ➔ Fertilisation ➔ Main plant body (Sporophytic) . have two, while monocots have one cotyledon .
Pteridophytes are classified as under Kingdom-Animalia
Pteridophytes • Animals are heterotrophic and multicellular organisms with
organs or tissues. Most are mobile or have a mobile life
Psilopsida Lycopsida Sphendosida Pteropsida
stage. All have a larval or embryonic stage of development.
(e.g. Psilotum) (eg. Selaginella ) (e.g. Equisetum) (e.g. Dryopteris Animals also exhibit different kinds of symmetry, i.e .
and Pteris) asymmetrical, spherical, radial and bilateral.
• Animals can be invertebrate (no backbone) or vertebrates
Gymnosperms
(with backbone) .
· Gymnosperms are plants with naked ovules. They include
• Intact vertebrates have two large groups, i.e. Pisces arid
medium size tree to giant redwood tree Sequoia. Plant
Tetrapoda .
1
body is diploid and divided into true root, stem and
Pisces (fishes) show locomotion via fins and can be
leaves. Root system is generally tap roots but in some
categorised to
plant such as in Pinus fungal association is in the form of
- Cyclostomata jawless fishes with 6-15 pairs of gill slits. They
Mycorrhiza and in Cycas, N2 fixing cyanobacteria in
are devoid of scales and have cartilagenous endoskeleton .
coralloid roots are found. Stem is erect and leaves are
- Chondrichthyses jaw bearing cartilagenous fishes like dogfish,
Pinnate in Cycas and needle like in conifers (Pinus). electric ray or shark.
' Heterospory is found in gymnosperms . These consist of - Tetrapods show locomotion via limbs and can be categorised to
two types of spores microspores and megaspores . • Amphibia tetrapods, thin, moist skin, use external
Male plant bear male cone which in made up of fertilisation, ectothermic, three-chambered heart and have
rnicrosporophyl Is. a brain , eyes and tympanum.
' Each microsporophyll contains microsporangia which • Reptilia live on land, have dry thick skin, internal skeleton ,
forms microspore . Microspore develops into red~ced male internal fertilisation , well developed kidneys that excrete
8arnetophyte (pollen grain) within microsporang1a . Female uric acid to conserve water, some with fou r-chambered
Plant bears megasporophylls that bear ovules. In ovules, heart (crocodile), ectothermic and breath through lungs
rnegasporangium develops female gametophyte that bear only.
 Magbook ~ General Scien•1t,
124
Type s of viruses on basis of genetic
alion, bones are honey-combed,
• Aves feathers mad e up of Iwratil1 Im insul material
plion al vision and enlarged 5 lernum.
four-chambered hea rt, excrete uric acid, exce - ds DNA viruses (e.g. Adenoviru ses
protei n, mammary glands, have Herp es viruses and Pox viruses). '
• Mammalia hair mad e up of keratin c1 11d
gh lungs only and - ss DNA viru ses (+) sense DNA (e.g
teeth , well deve loped dinp llrng m, brea th throu
hell these can be classified as Parvo viru ses) .
well -developec1 hormo11dl system . In a nuts - ds RNA virus es (e .g. Reoviruses)
Animal Kingdom _ (+) ss RNA viruses (+) _sense RNA (e.g_
Picornoviruses, Tongov1ruses),
Cellu l;11 Lev0I ol Tissue level of
- H ss RNA viruses H sense RNA (e.g.
organisalion
orgnnrs,1hon Orthomyxoviruses, Rhabdov1ruses)
I - ss RNA-RT viruses_(+) sense RNA Wifh
Pori'fera
DNA intermediate 111 life cycle (e.g.
Pseudocoe lom Coelomale
No body cavity between Retroviruses) ·
epidermis and gaslrodemis I _ ds DNA -RT viruses (e .g.
I
Coelenterata and Platyhelminthes
Nematoda
I I
Hepadnaviruses).

Economic Importance of Viruses

Coe/om formed from
Mesodermal cells pouches pinched off Diseases caused by viruses are as Under
from a single cell during from lhe endoderm
growth of lhe embryo Viral Disease of Plants
I
Annelida, Mollusca and Notochord present Causal Virus
Arthropoda Nolochord absent Diseases
I I Tobacco mosaic
Tobacco mosaic virus
Echinodermata Chordata
Papaya mosaic virus
Papaya mosaic
Abutilon mosaic Abutilon mosaic virus
Noloc hord presenl in Notochord replaced
by vertebral column Cucumber mosaic Cucumber mosaic
alleasl larval forms
in adults virus
bul very rudimentary
I Tomato leaf curl Tomato leaf curl virus
Vertebrata
Protochordata Potato virus-X
Potato mild mosaic

Exoskeleton of Exoskeleton of Exosk eleton of Potato rugose mosaic Potato vi rus-Y

E.xoskefelon of scales , Gills in larva,
lay eggs feathers , lay hair, externa_lears and Potato leaf roll virus
endoskeleton of bone/ lungs in most scale s and Potato leaf roll
outside water eggs outside water, mostly g1v1ng birth
cartilage breathing adults and slimy skin to live youngones Ratoon stunt of Ratoon stunt virus
/ / flight possible
through gills
I I . sugarcane
I Reptilia Aves Mammaha
Groundnut mosaic
Pisces Amphibia
e.g . Sea cow,
Rosette of groundnut
e.g. Snake, lizard e.g. Parrot, owl virus
e.g. Sea horse and e.g. Salamander
and penguin sea lion and man
frog and crocodile
common crap Citrus tristeza virus
Classificiation of animals friste za of citrus
Sugarcane mosaic Sugarcane virus-1
Disease Carrier Insects (Vectors)
- - -- -- - - - - - - - - - Bunchy top of banana Banana bunchy top
Insects Diseases virus
Insects Diseases
Rat flea Bubonic plague
Housefly Diarrhoea, leprosy,
typhoid, cholera, etc. Sand fly l(ala-azar

Mosquitoes Malaria, filariasis, dengue Tse-tse fly African sleeping sickness i Viroids and Prions
l Viroids and prions are just infecting
Kissing bug
fever, yellow fever, etc.
Chagas disease
Bed bug Typus fever

' ribonucleic acid and protein. They do not

Viruses
The term 'vi rus ' was given by Pasteur. It was
discovered by lvanowski in
l have any covering like virus or prokaryotic
and eukaryotic cells . Viroids are
·I' dc?nsideredfa s mhajor breakTthhreyough
parasites . They lack enzymes were
diseased tobacco plant. They are obligate Iscovery o 20t century.
necessary for the generation of energy. discovered by T Dienner in 1971 at
are dependent on the host for their Agricultural Research Service in Maryland.
• These are considered as non-living and
survival. They exist as crystal like forms outs
ide the host and once get I Viroids generally infect plant, while prions
tions which lead to death of the / are responsible for infect animal, i.e. mad
inserted, lead to dangerous and lethal infec
to possess small fragment of DNA cow disease, Creutzfeldt-Jacob disease,
individual. Most of the viruses are known
or RNA in single or double-stranded forms
DNA of the host organism.
and are capable to insert into the I Kuru disease, etc. - _...... ,
 pisease Pathog 011 Viral Diseases of Human Beings
AIDS HIV Reservoir
Vcttor/Eplde1nlology _ _ -- -
H11111 1u1 ~
Sprcci d tltro 11 n1i co11lac.1 with lnlecled body llui·d;. Dest~-ys im~u_ne
clclencc, rc5 ultiny In death hy Infec tion or cancer. Over 39 .S million
Chickenpo x Hu111 a 11 11 ,1 peopl e and 3. 6 million were Inf ec ted In India by 2007.
c P l'S vlr 11s Humans _ _ _ __
1 .
< \ oncc11 .
n , (lS / <' I ) Spread thrnugh contact with infected individual; rarely fatal. Vaccine
[bola Fil ov ir uscs approved in US in early 1995.
unknown - - - - - - - - - - · --
Acute haemorrhagic fever;~ ,r~s attacks connective tissu-e leading to
massive haemorrhage and death. Peak mortality is 50 -90%, if the
disease is untreated. Outbreaks confined to local regions of central
Hepa tit is- 8 (\ ir,11) Hep atitis- B ,/ -- - Africa.
( H BV) trus -- --- - - - - - - - - - - ------- ------- --- -·- -- -- - --
Humans Highly infectious through contact with infected body fluids . Vaccine
Herpes s~-;
Herp;~
Humans
avai Iable, can be fatal.
Virus (HSV) Fever, blasters; spread primarily through contact with infected saliva.
Very prevalent worldwide. Exhibits latency-the disease can be dormant
influenza for several years.
Humans and ducks Historically, a major killer (22 million died in 18 months in
1918-191 9); Wild asian ducks, chicken and pigs are major reservoirs.
The ducks are not affected by the flu, virus, which shuffles its antigen
-
'.\easies Pa~-an1yxovi1·uses_ _H _ _ __ _ _ _ _ _gene, while multiplyin g within them, leading to new flu strains.
_ _ _ _ _ __ __ _ _ __ _ _ _ _ _ _ __ __ __
umans Extremely contagious through contact with infected individuals.
Vaccine available, Usually contracted in childhood, when it is not
serious; more dangerous to adults.
1'.lon onucleosis Epstein- Barr Virus
Humans Spreads through contact with infected saliva. May last for several
( EBV)
weeks; common in young adults. Rarely fatal.
Mumps P ar~~yxo vi ~us · ·
Humans Spreads through contact with infected saliva. Vaccin.e available; rarely
fatal.
Pneumonia Influenza virus Humans Acute infection of the lungs, often fatal without treateme nt.
Poli o Polioviru s Humans Acute viral infection of the CNS that can lead to paralysis and is often
fatal. Salk's vaccine.
Rabies Rhabdov irus Wild and domestic An acute virul encephalomyelitis transmitt ed by the bite of an infected
Canidae (dogs, foxes, animal. Fatal if untreated .
valves and coyotes),
bats and raccoons.
Smallpox Variola virus Formerly humans, now Historica lly, a major killer; the recorded case of smallpox
was in
only exists into 1977. Last case of smallpox was found in 1984 but not confirmed, in
research labs-may be Bangladesh. A wo'rldwide vaccination campaign wiped out the disease
eliminate d . completely.
Ye llow fever Flaviviru s Humans and
Spread from individual to individua l by mosquito bites; a notable
mosquitoes
cause of. death during the construct ion of the Panama canal. If
untreated, this disease has a peak mortality rate of 60%.
- - - - - - - - - - - - - - - - · - - - - -- - - - - - - - - -
- - - - - - - -- - - - - - -- -- -
Chikungunya Chickeen gunya virus Arthralgi a (joint pain), sudden onset fever caused by the bite of Aedes
oegypti (mosquito).
Swine flu H N virus Similar to influenza
- 1 --
1
-- - - - - -- - - - - - -- -- - -- -and spread through sneeze of the infected person.
- - - - - - - -- - - ---:--:-- -:--
Dengue Dengue virus High fever, rashes on face, severe eye pain, joint pain caused by the
(flaviribo virus) bite of Aedes aegypti, Aedes allopictus and cu/ex fangans. Tornique t
test for diagnosis .
HPV Papillom a Human l<eratinocytes of the skin or muscons membranes.
virus
 Self CheC_~-
Build Your CC?_n_fid~n~E3- -- - ---------
7. Mycorrhizal bdiotechdnodlogsy1·teshabsecabueseen used .
1. H1N, virus is sometimes mentioned in the news with rehabilitating egra e mycorr~-~
refef'ence to which one of the following diseases? enables the plants to _ IIAs 20,~
p,J AIDS (b) Birds flu [IAS 2015) I. resist drought and increase absorptive area. ~
1cJ Dengue (d) Swine flu
11. tolerate extremes of pH.
2. l~1proper handling and storage of cereal grains and Ill. resist disease infestation. - .
oilseeds result in the production of toxins known as , t the correct answer using the codes given below
Se,ec {b) II and Ill
aflatoxins, which are not generally destroyed by normal (a) Only I
cooking process . Aflatoxins are produced by [IAS 20131 (c) I and Ill (d) All of these
,al Bacteria (b) Protozoa (c) Mould (d) Viruses
8. Consider the following statements ·u db
3. Which of the following diseases can be transmitted I. Dengue is a protozoan disease transm, e y
from one person to another through tattooing? mosquitoes.
[IAS 2013]
JI. Retro-orbital pain is not a symptom of dengue
I. Chikungunya II. Hepatitis-a
Ill. Skin rash and bleeding from nose and gums are some e
Ill. HI V-AIDS
the symptoms of dengue.
Select the correct answer using the codes given below Which of these statements given above is/are correct?
(a) Only I (b) II and II (c) I and Ill (d) All of these
(a) I and 11 (b} Only Ill
4. Which of the following statements is/are correct? (c) Only 11 (d) I and Ill
[IAS 2013]
I. Viruses lack enzymes necessary for the generation of 9. Consider the following statements
energy I. The common blue-green algae, Spirogyra and Ulothrix are
II. Viruses can be cultured in any synthetic medium. found in both freshwater ponds and oceans.
Ill. Viruses are transmitted from one organism to another by II. The Chameleon can look ahead with one eye and at the
biological vectors only same time look behind with another.
Select the co"ect answer using the codes given below Which of these statements is/are correct?
(a) Only I (b) Only II (c) I and Ill (d) All of these (a) Only I {b) Only 11
(c) Both I and II (d) Neither I nor II
5. Consider the following animals [IAS 2013]
t. Sea cow II. Sea horse 10. Bacteria are very use~~! now-a-days as many technique
Ill. Sea lion were developed to ut,llse them for extraction of useful
Which of the following is/are mammal/mammals? products. ~hich of the following bacteria are used for
(a) Only I (b) I and 111 the synthesis of antibiotics?
(c) II and Ill (d) I, 11 and 111 I. Bacillus II. Streptomyces
II I. Lactobacillus
6. Government of India encourages the cultivation of 'Sea Codes
buckthorn'. What is the importance of this plant? (a) Only I
(b) I and 11
(IAS 2012]
(c) II and Ill
I. It helps _in controlling soil erosion and in preventing {d) None of these
dessert1f1cat1on.
II. It is a rich source of biodiesel.
11.
f owing
ag?um is an important bryophytes. Consider the
Ph
0 11 statements about it·
Ill. It has nutritional value and is well adopted to live in cold I. It is a chief constituents of p~at.
areas of high altitudes. II. Very useful in trans t t· f ..
por a ion o wet or moisture reqwnng
IV Its timber is of great commercial value. products.
Which of these statements given above is/are correct? Ill. Also used for synthesis of antibiotics
(a) Only I (b) 11, Ill and IV Codes ·
(c) I and Ill (d) I, II, Ill and IV {a) I and II
{b) Only 111
(c) II and 111
{d) Only I
,../ 1. (d) 2. (c) 3. (b) 4. (a)
11. (a) 5. (b) 6. (c) 7. (d) 8. (c} 9. (b) 10. (/))