binomial classification - btbmd.abhiis.in/four/three/anmsc/binomial1.pdf · subclass spirotrichia...
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Binomial classification
KEY CONCEPT
Organisms can be classified based on physical similarities.
Why do we classify living Organisms?
To make this great biodiversity easier to
study!
• Classification is the grouping of organisms based on similarities of features.
• Taxonomy is the science of studyingclassification. It looks at features and tries to arrange them in a logical order.
Two main types of classification
Artificial classification: in which easily
observable characteristics are used.
such as colour, mode of locomotion,
habitat etc
Natural classification: which reflects
possible evolutionary relationships,
based on ancestry (phylogeny)
Early Classification – Aristotle (384 to 322 BC)
• Greek Scholar
• Divided animals into three groups
• Those that fly
• Those that swim
• Those that crawl or walk
Linnaean Classification System Developed in the mid 1700’s
by Swedish botanist named
Carolus Linnaeus.
Classifies all organisms as
animals or vegetable (plant)
Gave all organisms a two part
Latin name.
• Why did Carolus Linnaeus develop this system?
The yellow and white
flower with many
small petals
The yellow and
white flower with
no obvious scent
Carl Linnaeus – Chrysanthemum leucanthemum
The pretty flower with a
fuzzy yellow center
surrounded by white
petals which attracts
small bees.
How it’s organized
• Linnaean
classification
system has seven
levels.
• Each level is
included in the level
above it
• Levels get
increasingly specific
from kingdom to
species.
A taxon (taxa – plural) is a group of organisms in a
classification system.
A ‘species’ is the fundamental taxon
Groups of similar species form the next largest taxon
called a ‘genus’.
Groups of similar genera form the next largest taxon
called a ‘family’
…and so on, up to the largest taxon = Kingdom.
Seven Levels of classification
1. Kingdom
2. Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species
King Phillip Called
Others From Germany,
Singapore.
Limitations of Linnaean Classification
• Physical similarities are not always a result
of a species being closely related
• Unrelated species can evolve similar traits.
Modern classifications uses genetic similarities.
Recent DNA research has changed
some long standing classifications.
Binomial nomenclature
• A naming system that gives each
species a unique two part name.
• Uses Latin and Greek words.
• Uses the Genus and Species as first
and last name.
White oak:
Quercus alba
• Scientific names help scientists to communicate.
– Some species have very similar common names.
– Some species have many common names.
Advantages over common names:
• Genus - includes one or more physically similar species
that are closely related.
– Always written in italics and Capitalized
• Species – a group of organisms that can successfully breed
and produce offspring.
– Always written in italics and lowercase
Tyto alba
Binomial NomenclatureFamily
Family Felidae (Cats)
Tiger - Panthera tigris Lion - Panthera leo Kitten – Felis domesticus Cougar – Felis concolor
Genus and species
are always italicized
OR underlined if
hand written
First letter of the
genus is capitalized First letter of the
species is lowercase
Let's try some simple naming - Latin
The brown caterpillar Noun first descriptor second.
i.e. caterpillar brown
Eruca castane
Let's try some simple naming - Greek
The spotted reptile
Herpeto halio
Let's try some simple naming - Greek
Reptile with a flat nose.
Herpeto platyrhino
Types of Invertebrates
The invertebrates are a group of animals (and animal-
like organisms) that do not have a backbone.
♦ The group of invertebrates without specific organs
is referred to as the lower invertebrates. For
example, Protozoans and Porifera, while the higher
developed invertebrates have a true coelom like
mollusks, annelids, echinoderms, and arthropods.
♦ Generally, the invertebrates are divided into four
groups, based on their cellular composition and
organization, namely Protozoa, Mesozoa, Parazoa
and Metazoa
Protozoa
• They are for the most part of their lives
unicellular, i.e. made up of one cell
• They are also described as being acellular i.e.
not divided into cells (non-cellular).
• Their vital functions are carried out by
organelles.
Mesozoa (Greek: mesos =
middle; zoon = animal)
• The name was given because mesozoans are
thought to be intermediate between true
multicellular animals and protozoans (single-
celled/acellular organisms).
• Their bodies are cellular.
• They do not have more than two cell
‘layers’; the outer layer ciliated and the
inner reproductive.
Mesozoa
• They are bilaterally symmetrical.
• They have no organs.
• They have no body cavity.
• Gametes and agametes are produced from special
cells, which form the central mass of the body.
Parazoa
• Multicellular invertebrates, which possess
collared flagellated cells that make them
unique among the other multicellular
invertebrates.
• The many cells in their body are not
organized into tissues and organs.
• They are therefore at the cellular level of
organization.
Metazoa
• Invertebrates with marked cellular differentiation.
• There are two levels of organization in this group:
Diploblastic – includes animals with two cell layers showing
tissue level of organization, where the body is composed of an
inner endoderm and outer ectoderm.
Triploblastic – includes animals with three layers showing
organ level of organization; they possess a third body layer, the
mesoderm between the outer ectoderm and inner endoderm.
Characteristic features of
Protozoa
1. SMALL, MICROSCOPIC.
2. PROTOPLASMIC GRADE OF
ORGANIZATION.
3. UNICELLULAR, MULTINUCLEATED
(MONOMORPHIC OR DIMORPHIC).
4. SOLITARY, FORMING LOOS COLONY.
5. SYMMETRY – NONE
Characteristic features of
Protozoa
6. SUBCELLULAR PHYSIOLOGICAL
DIVISION OF LABOUR.
7. LOCOMOTION BY LOCOMOTORY
ORGANS LIKE CILLIA,FLAGELLA OR
THROUGH PSEUDOPODIA.
8. NUTRITION HOLOZOIC OR
HOLOPHYTIC OR PARASITIC OR
SAPROZOIC
DIGESTION
9. DIGESTION : INTRACELLULAR
THROUGH FOOD VACUOLES.
10. RESPIRATION AND EXCRETION:
THROUGH GENERAL BODY SURFACE
OR TROUGH CONTRACTILE
VACUOLES.
11. REPRODUCTION – ASEXUAL –
BINARY OR MULTIPLE FISSION.
SEXUAL – CONJUGATION
ENCYSTMENT MAY BE.
Classification of the
Protozoans
They are broadly divided into four subphyla based mainly on their organelles
and modes of locomotion as follows:
♦ Sub-Phylum: Sarcomastigophora
♦ Sub-Phylum: Sporozoa
♦Sub- Phylum: Cnidospora
♦Sub- Phylum: Ciliophora
SubPhylum
Sarcomastigophora
Uses flagella or pseudopodia as a means of
locomotion. Ex Amoeba, Entamoeba,
Euglina,Volvox single nucleus(monomorphic),
Asexual reproduction is by longitudinal binary fission.
A. Superclass MASTIGOPHORA
B. Superclass OPALINATA
C. Superclass SARCODINA
A. Superclass
MASTIGOPHORA
• Body is covered by pellicle; locomotory
organelles are flagella;
• Asexual reproduction by longitudinal
binary fission.
• It includes two classes –
Phytomastigophora and
Zoomastigophora
Superclass MASTIGOPHORA1. Class
Phytomastigophorea
• Some are with chlorophyll
bearing chloroplasts
• Nutrition is holophytic
• Reserve food is paramyl-
um
• Includes euglenoids and
dinoflagllates
2. Class
Zoomastigophorea
• Mostly parasitic;
• Chloroplasts are absent;
nutrition is holozoic
• saprozoic or parasitic,
Reserve food is glycogen
or volutin.
Class Phytomastigophorea
(Phytoflagellates): 6
orders
• Order 1.
Cryptomonadida-
Cryptomonas
• Order 2.
Dinoflagellida-
Noctiluca.
Class
Phytomastigophorea• Order 3. Euglenida -
Euglena
• Order 4.
Chrysomonadida -
Dinobryon
• Order 5. Volvocida -
Volvox
• Order 6.
Chloromonadida -
Chattonella
Class
Zoomastigophorea (Zooflagellates)- 2
orders
Order 1. Choanoflagellida –ProterospongiaOrder 2. Kinetoplastida-Leishmania, Trypanosoma.
B. Superclass OPALINATA
• Commensals or
parasites in the gut of
anurans.
• Body is covered by
oblique rows of cilia
but without
infraciliary system.
• Some are binucleate,
others are
multinucleate but
homokaryotic.
• Examples Opalina
C. Superclass SARCODINA
(=RHOZOPODA)
•Locomotion is brought about by pseudopodia.• It includes three classes –
• Rhizopodea
•Piroplasmea
• Actinopodea
Class Rhizopodea•It includes amoebas, foraminiferans.
• Amoebas have lobopodia or filopodia
• Foraminiferans have reticulopodia.
•In amoebas body is soft.
• Foraminiferans have a calcareous porous shell.
Class Piroplasmea
Parasitic; locomotory structures absent; spores are
absent.
Example: Babesia (causes red water fever in cattle)
Class Actinopodea
These are the ray footed protozoans.
• Locomotory structures are axopodia.
• Skeleton consists of siliceous shell (Radiolaria)
or strontium sulphate spines (Acantharea) or siliceous
shell or radiating needles (Heliozoa).
• Silicious shells of radiolarians form ooze
.
Examples: Collozoum (radiolarian) Actinophrys
(heliozoan) Acanthometra, Actinosphaerium
Sub-Phylum: Sporozoa
Locomotory organs absent, spores usually
present, endoparasitic) eg. Eimeria, Monocystis,
Plasmodium
It includes three classes - Telosporea,
Toxoplasmea and Haplosporea.
Class: Telosporea
•Spores without polar capsules and filaments
•Sporozoites are long
• Subclass Gregarinea (Monocystis; Gregarina).
• Subclass Coccidia (Plasmodium).
Class: Haplosporea
•Spores are present and are amoeboid,
•Reproduction is only asexual, by multiple
fission.
• Each spore contains singl e sporozoite o
Example: Haplosporidium
Class: Toxoplasmea
Body covered by two layered pellicle
• Only asexual reproduction, by endodyogeny.
• It is internal budding wherein two daughter
cells are produced within a mother cell and the
mother cell is destroyed in the process,
Example: Toxoplasma
Sub- Phylum: Cnidospora
• Parasitic.
• No special locomotory structures.
• Spores are provided with one or more polar filaments,
which are useful for attachment to the host.
• It includes two classes - Myxosporidea and
Microsporidea
Sub- Phylum: Cnidospora
Class Myxosporidea
• Extracellular parasites of
cold blooded vertebrates.
• Spores with typically two
capsules each with single
polar filament.
• Example: Myxidium
Class Microsporidea
• Intracellular parasites in
fish.
• Spore with one
intrasporal or 1 -2
intracapsular filaments.
• Example: Nosema
bombycis
Sub- Phylum: Ciliophora•Complex protozoans.
• Cilia are useful in locomotion and food capture.
• Dimorphic nuclei - macronucleus (vegetative and polyploid) and micronucleus (reproductive and diploid),
•Sexual reproduction by conj ugation, which brings about nuclear reorganization.
•Only class under this subphylum is Class Ciliata. o
Example: Paramecium, Balantidium.
Class Ciliata
Subclass Holotricha (Paramecium; Balantidium).
Subclass Peritricha (Vorticella).Subclass Suctoria (Ephelota; Podophrya).Subclass Spirotrichia (Stentor)
Class Ciliata
Subclass Holotricha
• Buccal cillia absent.
• Body cillia simple and
uniform.
• Orders- 6
1.Gymnostomatida
2.Trichostomatida (Balantidium)
3.Chonotricha
4.Apostomatida
5.Astomatida
6.Hymenostomatida
(Paramecioum)
Subclass Peritricha
• Adult wothout body cillia.
• Apical end with buccal
cillia.
• Oreder
• Peritrichida (Vorticella)
Subclass Suctoria
Subclass Suctoria
• Sessile and stalked body.
• Young with cillia, adult
with suctorial tentacle
• Order- Suctoria
• ex Podophyra
Subclass Spirotrichia
• Reduced body cillia.
• Buccal cillia well marked.
• Ex Nyctotherus
• Orders- 3
• Hetertrichida
• Oligotrichida
• Hypotrichida