Living world NCERT Flashcards
Darwin of the 20th century is
Ernst Mayor
Ernst Mayor pioneered the currently accepted definition of _____
He was also given 3 prizes regarded as ______
Biological species
Triple crown of biology
—- is the science of life forms and living processes.
Biology
The living world
comprises an amazing —-of living organisms.
diversity
Early man could
easily perceive the difference between —- and —-.
inanimate matter and living organisms
Early man —- some of the inanimate matter (wind, sea,fire etc.) and some among the animals and plants. A common feature of all such forms of inanimate and animate objects was the sense of —– that they evoked
deified (worshipped)
awe or fear
The description of living organisms including
human beings began ——.
much later in human history
Societies which indulged in —– view of biology could register limited progress in biological knowledge
anthropocentric (considered humankind as the most imp element of existence)
Systematic and —–
description of life forms brought in, out of —-, detailed systems
of identification, nomenclature and classification.
monumental
necessity
The biggest spin off
of such studies was the recognition of the ——among living organisms both horizontally and vertically
sharing of similarities
That all present day
—— are related to each other and also to all organisms that ever lived on this earth, was a revelation which humbled man and led to cultural movements for —–
living organism
conservation of biodiversity
The —– conflict and cooperation among members of a population and among populations of a community
or even the —– inside a cell make us deeply reflect on – what
indeed is life?
ecological
molecular traffic
Meaning of life: The first
is a —– and seeks answer to what living is as opposed to the
non-living, and the second is a —– one, and seeks answer to what the purpose of life is.
technical one
philosophical
When we try to define ‘living’, we conventionally look for —— exhibited by living organisms.
distinctive
characteristics
—-, reproduction, ability to sense environment and mount a —– come to our mind immediately as unique features of living organisms.
One can add a few more features like —-, ability to self-replicate, —-, interact and — to this list.
Growth,
suitable response
metabolism
self-organise
emergence
All living organisms grow. Increase in —and increase in —- are twin characteristics of growth.
mass, number of individuals
A multicellular organism grows by —–.
cell division
In plants, this growth by cell division occurs
—– throughout their life span.
continuously
In animals, —- is seen
only up to a certain age. However, cell division occurs in certain tissues to —– .
growth
replace lost cells
Unicellular organisms grow by —– . One can easily observe this in —– cultures by simply counting the number of
cells under the microscope
cell division
in vitro
In majority of higher animals and plants,
growth and reproduction are mutually —- events.
exclusive
One must remember that increase in —- is considered as growth.
body mass
Non-living objects also grow if we take —— as a criterion for growth.
Mountains, boulders and sand mounds do grow
increase in body mass
Growth exhibited by non-living objects is by —-on the surface. In living organisms, growth is from —.
accumulation of material
inside
Growth is a defining property of living organisms. T/F
False
because non living also exhibit extrinsic growth
Yet growth is a characteristic is a living system
Reproduction is a characteristic of living organisms. T/F
True.
It is not a defining character but it is characteristic
In multicellular organisms, reproduction refers to the —- possessing features more or less similar to those of parents. Invariably and implicitly we refer to —-reproduction.
production of progeny
sexual
Fungi multiply and spread easily due to the millions of —- they produce.
asexual spores
In lower organisms like
——- and—- , we observe budding.
yeast and hydra
In Planaria (flat worms), we observe —–, i.e., a fragmented organism regenerates the lost part of its body and becomes, a new organism.
true regeneration
The —-, —- and — all easily multiply by fragmentation.
fungi, filamentous algae, the protonema of mosses,
When it comes to —-organisms like bacteria, unicellular algae or Amoeba reproduction is synonymous with growth, i.e., —————
unicellular
increase in number of cells
There are many organisms which do not reproduce (—-, —-, —- etc).
mules, sterile worker bees, infertile humans
Another characteristic of life is metabolism. All living organisms
are made of —-.
chemicals
These chemicals, small and big, belonging to
various classes, sizes, functions, etc., are constantly being made and——-
These conversions are chemical reactions or —–.
changed into some other biomolecules.
metabolic reactions
There are thousands of metabolic reactions occurring —- inside all living organisms, be they unicellular or multicellular.
simultaneously
All plants, animals, fungi and microbes exhibit
metabolism. The sum total of all the ——occurring in our
body is metabolism
chemical reactions
No non-living object exhibits metabolism. T/F
True
Metabolic reactions can be demonstrated outside the body in —- systems.
cell-free
An isolated metabolic reaction(s) outside the body of an organism, performed in a test tube is —–
neither living nor non-living.
Isolated metabolic reactions —- are not living things but surely living reactions.
in vitro
Cellular organisation of the body is the — feature of life forms.
defining
Perhaps, the most obvious and technically complicated feature of all
living organisms is their —
and respond to these environmental stimuli which could be physical,
chemical or biological.
ability to sense their surroundings or environment
We sense our environment through our — .
sense organs
Plants respond to external factors like —, —-, —–,—-, —–, etc.
light, water, temp, other orgs, pollutants
All organisms, from the prokaryotes to
the most complex eukaryotes can sense and respond to —- .
environmental
cues
—- affects reproduction in seasonal breeders, both plants and animals.
Photoperiod
All organisms handle —-entering their bodies. All
organisms therefore, are ‘aware’ of their surroundings.
chemicals
Human being is the only organism who is aware of himself, i.e., has —
self-consciousness
Consciousness is the defining property of living
organisms. T/F
True
When it comes to human beings, it is all the more difficult to define
the —- state.
living
We observe patients lying in coma in hospitals virtually supported by machines which replace heart and lungs. The patient is otherwise brain-dead. The patient has no —-
self consciousness
All living phenomena
are due to —-.
underlying interactions
Properties of tissues are not present in the constituent cells but arise as a result of——–.
interactions among the constituent cells
Properties of cellular organelles are not present in the molecular constituents of the organelle but arise as a result of —-
interactions among the molecular components comprising the organelle.
These interactions result in emergent properties at a —-level of
organisation. This phenomenon is true in the hierarchy of —- at all levels.
higher
organisational complexity
Therefore, we can say that living organisms are
self—, — and —-interactive systems capable of responding to external stimuli
replicating, evolving and regulating
—- is the story of life on earth. Biology is the story of —— on earth.
Biology, evolution of living organisms
All living organisms – present, past and future, are linked to one another by the sharing of the —-, but to varying degrees.
common genetic material
Each different kind of plant, animal or organism that you see, represents a
—–.
species
The number of species that are known and described range
between ——. This refers to —- or the number and
types of organisms present on earth.
1.7-1.8 million
biodiversity
We should remember here that as we explore new areas, and even old ones, new organisms are continuously being —-.
identified
We know the plants and animals in our own area by their —- names.
These names would —from place to place, even within a country.
local, vary
There is a need to standardise the naming of living organisms so that: —-.
This process is called —-.
a particular organism is known by the same name all over the
world
nomenclature
Nomenclature or —- is only possible when the organism is described correctly and we
know to what organism the name is attached to. This is —–.
naming
identification
In order to facilitate the study, number of scientists have established —- to assign a scientific name to each known organism. This is
acceptable to — all over the world.
procedures
biologists
For plants, scientific names are based on agreed principles and criteria, which are provided in —–.
International
Code for Botanical Nomenclature (ICBN)
Animal taxonomists have evolved —–.
International Code of Zoological
Nomenclature (ICZN)
The — names ensure that each organism has only one name.
scientific
— of any organism should enable the people (in any part of the world) to arrive at the—- name. They also ensure that such a name has not been used for any other known organism.
Description, same name
Biologists follow —-principles to provide scientific names to known organisms.
universally accepted
Each scientific name has two components – the
— name and the —-. This system of providing a name with two components is called —-nomenclature
Generic, specific epithet
Binomial
This naming (Binomial nomenclature) system given by —- is being practised by biologists all
over the world. This naming system using a two word format was found convenient
Carolus Linnaeus
Biological names are generally in — and written in —-. They are Latinised or derived from Latin irrespective of their
origin
Latin, italics
The first word in a binomial name represents —–
genus
Both the words in a biological name, when handwritten, are
—–, or printed in italics to indicate their —-
origin.
separately underlined
Latin
The first word denoting the genus starts with a capital letter while the specific epithet starts with a — letter.
small
Name of the author appears after the specific epithet, i.e., at the end of
the biological name and is written in an —- form,
abbreviated
Mangifera indica Linn. indicates that this species—–
was first described by Linnaeus.
It is necessary to devise some means to study all the organisms because
It is nearly impossible to study all the living organisms without classification
—– is the process by which anything is grouped
into convenient categories based on some —– characters
Classification
easily observable
The scientific term for these categories is —–.
taxa
Taxa can indicate
categories at —- levels. ‘Plants’ – also form a taxa. ‘Wheat’ is also a taxa. They represent taxa at different levels
very different
Based on —-, all living organisms can be classified into different taxa. This process of classification is —.
characteristics
taxonomy
—- and — structure, along with the structure of —-, —-and —– information of organisms are essential and form the basis of modern taxonomic studies.
External and internal
structure of cell
development process
ecological
characterisation, identification, classification and nomenclature
are the processes that are basic to —-.
taxonomy
Taxonomy is not something new because:
Human beings have always been interested in knowing about the organisms, with reference to their own use.
In early days, human beings needed to find sources for their basic needs of —-, —- and —.
Hence, the earliest classifications were based on the ‘—-’ of
various organisms.
food, clothing
and shelter
uses
Human beings were, since long, also interested in the relationships among the orgs.. This branch of study was referred to as
—-.
systematics
The word systematics is derived from the Latin word ‘—-’ which means systematic arrangement of organisms.
systema
Linnaeus used —– as the title of his publication. The scope of systematics was later enlarged to include identification, nomenclature
and classification. Systematics takes into account—- between organisms
Systema Naturae
evolutionary relationships
Classification is not a single step process but involves hierarchy of steps in which each step represents a —- .
rank or category
Since the category is a
part of overall taxonomic arrangement, it is called the taxonomic category
and all categories together constitute the —-
taxonomic hierarchy
Each category, referred to as a unit of classification, in fact, represents a rank
and is commonly termed as —-
Taxon
Insects represent a group of organisms sharing common features like
—- pairs of jointed legs. Therefore they were given a rank/category.
- Groups represent —-.
- Category further denotes rank. Each rank or taxon, in fact, represents a —-.
Three
Category
unit of classification
These taxonomic groups/
categories are —— and not merely morphological
aggregates
distinct biological entities
Taxonomical studies of all known organisms have led to the development of common categories such as kingdom, phylum or —-(for plants), class, order, family, genus and species.
division
All organisms,
including those in the plant and animal kingdoms have —- as the lowest category.
species
The basic requirement to place an organism in a category is the —– of an individual or group of organisms. This helps in
identifying similarities and dissimilarities among the individuals of the —–
knowledge
of characters
same and diff kinds of orgs
Taxonomic studies consider a group of individual organisms with
—– as a species.
fundamental similarities
One should be able to distinguish one species from the other closely related species based on the —- differences.
distinct
morphological
All the three names, indica, tuberosum and leo, represent the —-, while the first words
Mangifera, Solanum and Panthera are—- and represents another
higher level of taxon or category. Each genus may have one or more than
one specific epithets representing different organisms, but having
morphological similarities. For example, Panthera has another specific
epithet called tigris and Solanum includes species like nigrum and
melongena. Human beings belong to the species sapiens which is
grouped in the genus Homo. The scientific name thus, for human being,
is written as Homo sapien
specific epithets
genera
Each genus may have —- no, of specific epithets representing different organisms, but having —-similarities.
one or more
morphological
Panthera has another specific epithet called —- and Solanum includes species like —- and —.
tigris and leo
nigrum and
melongena
Human beings belong to the species —- which is grouped in the —– Homo.
sapiens
genus
Genus comprises a group of related species which has —- characters
in common in comparison to species of other genera.
more
We can say that
genera are aggregates of ———.
closely related species
Potato and brinjal are two different species but both belong to the genus —-.
Solanum
Lion (Panthera leo), leopard (—–) and tiger (P. tigris) with several
common features, are all species of the genus Panthera. This genus differs from another genus —-which includes cats
P. pardus
Felis
Family, has a group of related genera with —-
number of similarities as compared to genus and species.
still less
Families are characterised on the basis of —- and — features of plant species.
both vegetative and reproductive
Among plants for example, three different genera —–, —- and —, are placed in the family Solanaceae.
Solanum, Petunia, Datura
Among animals
for example, genus Panthera, comprising lion, tiger, leopard is put along
with genus, Felis (cats) in the family —–.
Felidae
Two different families – Felidae has —–
and Canidae has—–, respectively
Cats, dogs
Generally, order and other higher taxonomic categories are identified based on the ——–.
aggregates of characters
Order being a higher category, is the assemblage of families which exhibit a —- similar characters.
few
Plant families
like ——-, ——– are included in the order
Polymoniales mainly based on the —–characters.
Solanaceae, Convolvulaceae
floral
The animal
order, ——, includes families like Felidae and Canidae
Carnivora
—- includes related orders.
Class
Primata comprising —,— and — is placed in class
Mammalia along with order Carnivora that includes animals like
tiger, cat and dog.
monkey, gorilla and gibbon
Classes comprising animals like fishes, amphibians, reptiles, birds along with mammals constitute the next higher category called ——-
In plants classes with similar features constitute —–
Phylum
Division
All animals belonging to various phyla are assigned to the
highest category called ———- in the classification
system of animals.
Kingdom Animalia
The Kingdom Plantae, on the other hand, is
distinct, and comprises all plants from various ——.
divisions
Taxonomists have also
developed —– in this hierarchy to facilitate more sound and scientific placement of various taxa.
sub-categories
As we go higher from species
to kingdom, the number of common characteristics goes on
decreasing
The problem of classification becomes more complex in —- taxa because greater the difficulty of determining the relationship to other taxa at the same level.
higher
Family and order of humans-
Homonidae, Primata
Genus and Order of Housefly
Musca, Diptera
Order, class and division of Mango
Sapindales, Dicotyledon, Angiosperms
Name, Family and class of wheat
Triticum aestivum, Poaceae, Monocotyledon
