Transcript DIVERSITY IN LIVING ORGANISMS

DIVERSITY IN
LIVING
ORGANISM S
Kingdom : Monera
Nucleus :
•
(a) Organisms of this kingdom do not possess a welldeveloped nucleus.
(b) Nucleolus and nuclear membrane are absent.
(c) The genetic material occurs in the form of a mass of
nucleoproteins.
(2) Organelles of cytoplasm :Membranous organelles are
also absent in the cell.
(1)
(3) Types :
Bacteria are the sole members of the kingdom Monera.
This kingdom is divided into two divisions.
(a) Schizophyta or Bacteria,
(b) Cyanophyta
(4)Nutrition:
Bacteria live mainly as transformers, decomposers and
also as parasites, e.g. E.coli
Cyanophyta are also known as blue-green algae or
cyanobacteria. They are autotrophic and posses
photosynthetic pigments.
e.g. Spirulina, Oscillatoria.
Kingdom : Protista
• (1) Structure :
Organisms are unicellular or multicellular.
• (2) Nucleus :
They possess a well developed nucleus.
• (3) Organelles :
Membranous organelles like mitochodria,
golgibody etc. are present. They do
not exhibit division of labor.
• (4) Method of nutrition :
They are autotrophic, heterotrophic and
symbiotic methods of nutritions.
Accordingly, protista are classified into
autotrophs, phagotrophs or heterotrophs
and symbionts.
• e.g. Algae, Protozoa and Fungi.
Kingdom: Fungi
• (1) Cellwall :
It is made up of chitin
and cellulose or chitin.
• (2) Organelles :
Mitochondria with flat
cristae, organelles like
lomasomes which are
responsible for chemical
constitution or Cellwall
and Scattered ribosomes
are representative
characters of fungi.
• The fungal cell wall is composed
of glucans and chitin
• (3) Nutrition :
They exhibit saprophytic or parasitic mode of
nutrition.
• (4) Body organization :
• Their body is called mycelium and the filament –
like structures are called
hyphae. (singular : hypha)
•
• (5) Example : Yeast, mucor.
The chart given below briefly outlines the classification of
The plant kingdom
The Animal Kingdom is divided in several phyla mainly on the basis of the cell
organisation, symmetry, presence or absence of notochord and body cavity.
Animals are arranged progressively from simple single-celled protozoans to
highly complex mammals. Given below are some of the main characteristics of
each phyla.
Phylum: Porifera
(the sponges)
• The simplest multicellular animals. The cells are
loosely held together and do not form tissues
• Aquatic in habitat (mostly marine)
• The body is covered with pores
• Food and oxygen enter the organism along with
water into a canal system
• They are non-motile animals attached to some
solid support
• Reproduction may be sexual, asexual or
budding
• Example: Sycon, Spongilla, Euptectella
Phylum: Coelenterate
• These animals live in water
• Colentrates show more body
desigh differentiation
• The body is made up of two layers
of cells- one makes up cells on the
outside and other makes the inner
lining of the body
• Some of the species live in
colonies(corals) while others have a
solitary life-span
• E.g. Sea anemone, Jellyfish
Phylum:
Platyhelminthes
(Flatworms)
• Simplest triploblastic organisms showing bilateral
symmetry
• Mostly parasites in other animals
• Body in dorsoventrally flat and leaf-like or ribbon-like
with bilateral symmetry
• The body cavity has only one opening which serves as
both the mouth and the anus
• Example: Planaria, Liver Fluke, Tape Worm
Phylum: Nematoda
• Triploblastic body
showing bilateral
symmetry
• Parasitic or free living
• Body is long, smooth
and cylindrical
• Alimentary canal begins
with the mouth and
ends with the anus
• Example: Ascaris
(Round worm),
Enterobius (Pinworm)
Phylum:
Annelida(Segmented
worms)
)
• These animals are found in a
variety of habitats- fresh water,
marine water as well as land
• They are bilaterally symmetrical,
triploblastic animals
• Annelids are the first animals
with true body cavity
• They have metameric
segmentation with extensive
body differentiation
• E.g. Earthworm, Leech
Phylum Arthropoda
(animals with jointed legs)
• This is the largest phylum with almost
80% of the animal kingdom
• Body is bilaterally symmetrical and
segmented. It is divided into head,
thorax and abdomen
• Possess jointed legs which may be
modified for walking, swimming
feeding and feeling
• The coelomic cavity is blood-filled
• Open circulatory system is present
• E.g. Prawn, Butterfly, Spider,
Mosquito
Phylum: Mollusca (soft-bodied
animals)
• Aquatic in habitat but some land
forms are also seen
• Bilateral symmetry is present
• The coelomic cavity is reduced
and there is little segmentation
• Open circulatory system is
present and kidney-like organs
for excretion
• The soft body is supported by a
hard shell
• Locomotion is brought about
with muscular foot
• E.g. Octopus, Pila
Phylum Echinodermata
(spiny-skinned animals)
• Marine in habitat
• Body is triploblastic and has a
coelomic cavity
• They have a peculiar water-driven
tube system for locomotion
• Skeleton is made of hard calcium
carbonate structures
• E.g. Star fish, Sea cucumber
Protochordata
• They are exclusively marine,
triploblastic and coelomate
• Bilateral symmetry is present
• A long rod-like support
structure called notochord is
present at some stage of life.
• E.g. Balanoglossus
Sub-phylum Vertebrata
•
•
•
•
•
•
•
•
This includes the majority of chordates
Head is prominent
Nervous system and exoskeleton are highly developed
Notochord is replaced by a jointed vertebral column
Two pairs of appendages (limbs)
Aquatic animals have gills
Vertebrates are grouped into five classes:
Pisces, Amphibia, Reptilia, Aves and Mammalia
Class: Pisces
• These are fishes and exclusively
water living animals
• The body is covered with scales
• Body - streamlined
• Fins – present, limbs -absent
• Muscle tails is present which is
used for movement
• Respiration through gills
• Cold-blooded, two chambered heart
• egg laying.
They are two types based on
• The nature of their skeletons:
1) Cartilaginous fish- Their skeleton is
made of cartilage such as sharks, rays etc.
2) Bony fish- Their skeleton is
made of bones such as Rohu,
Seahorse etc.
Class: Amphibia
•
•
•
•
•
Live in both water and on land
Respiration is by gills, lungs or skin
3 chambered heart
Is cold blooded
Have two pairs of pentadactyl (5 digit) limbs
which may be absent in some cases
• They lay eggs
• E.g. Frog, Salamanders
Class: Reptilia
•
•
•
•
•
Mostly terrestrial
Heart is 3 chambered, is cold blooded
Breathe through lungs
Body covered with scales
Have two pairs of pentadactyl (five digit)
limbs which are absent in snakes
• They lay eggs
• The heart is three-chambered
• E.g. Snakes, Lizards, Crocodiles.
Class: Aves (birds)
• Arboreal in habitat i.e., they live on
trees
• Warm blooded. 4 chambered heart
• Body covered with feathers
• Lungs have membranous
extensions called air sacs to make
the body light
• Mouth is surrounded by a beak.
Teeth are absent
• Fore-limbs are modified into wings
• E.g. Sparrow, Pigeon
Class: Mammalia
(Mammals)
•
•
•
•
•
•
•
•
Most intelligent of all organisms
Warm blooded with 4 chambered heart
Give birth to young ones
The mother suckles her young ones on
milk secreted by special glands called
mammary glands
Body covered with hair
Have two pairs of pentadactyl limbs
Breathe through lungs
E.g. Humans, Whales, Elephant
Nomenclature
•
Carl Linnaeus, father of modern botany, was a Swedish naturalist who laid the
foundation of modern classification and nomenclature in 1758. He devised a
binomial system of nomenclature (naming system) in which an organism is
given two names:
•
A generic name (name of genus) which it shares with other closely related
organisms which has features similar enough to place them in the same
group.
•
A specific name (name of species) which distinguishes the organism from all
other species. No other organism can have the same combination of genus
and species.
•
The scientific name derived by using the system of nomenclature is followed
all over the world as they are guided by a set of rules stated in the
International Code of Nomenclature
• The scientific name derived by using the
system of nomenclature is followed all
over the world as they are guided by a set
of rules stated in the International Code of
Nomenclature.
• E.g. Mango (Mangifera indica)
• Tiger (Panthera tigris)
The end