Question 1:
Conservation of biodiversity is important for:
- Animals
- Animals and plants
- Plants
- All organisms
Answer:
(d). All organisms
Question 2:
Threatened species are those which:
- threaten others
- Lion and tiger
- are abundant in number
- are suffering from the danger of extinction
Answer:
(d). are suffering from the danger of extinction
Question 3:
National parks and sanctuaries are established for the purpose of:
- Recreation
- Hunting
- Pets
- Conservation
Answer:
(d). Conservation
Question 4:
Biodiversity is richer in:
- Tropical regions
- Temperate region
- Polar regions
- Oceans
Answer:
(a). Tropical regions
Question 5:
In which of the following countries,‘Earth Summit’ was held?
- U.K.
- Brazil
- Mexico
- China
Answer:
(b). Brazil
Question 6:
What is biodiversity?
Answer:
Biodiversity itself is a combination of two words, Bio (life) and diversity (variety). In simple terms biodiversity is the number and variety of organisms found within a specified geographical region. It refers to the varieties of plants, animals and micro-organisms, the genes they contain and the ecosystems they form. It relates to the variability among living organisms on the earth.
Question 7:
What are different levels of Biodiversity?
Answer:
Biodiversity exists at three different levels :
(a) Species Diversity : It is reflected by morphological, physiological and genetic features.
(b) Genetic Diversity : It comprises genetic variations within a species.
(c) Ecosystem Diversity : It is reflected in diverse bio-geographic zones such as lakes, deserts, coasts etc.
Question 8:
What do you understand by ‘hotspots’?
Answer:
The diversity of species can be measured through its richness, abundance and types. Some areas are more rich in species than others. Areas rich in species diversity are called hotspots of diversity.
Question 9:
What is the importance of animals to humankind?
Answer:
Herbivorous and carnivorous animals provide different products. In early history, man was dependent upon cattle rearing. The animals used to eat grass and provide meat and dairy products to feed population.
Question 10:
What do you understand by ‘exotic species’?
Answer:
Species which are not the natural inhabitants of the local habitat but are introduced into the system, are called exotic species. It is not native to a given area. It can be a plant, animal or insect that has been brought to an area, often by immigrants.
Question 11:
What are the role played by Biodiversity in shaping the nature?
Answer:
Importance of biodiversity
Biodiversity has contributed in many ways to the
development of human culture, and, in turn, human
communities have played a major role in shaping the
diversity of nature at the genetic, species, and
ecological levels. There are four roles—
(1) ecological,
(2) economic
(3) ethical and
(4) scientific—played by biodiversity which are discussed below :
1. Ecological role of biodiversity
Species of many kinds perform some function or
the other in an ecosystem. Nothing in an ecosystem
evolves and sustains without any reason. That means,
every organism besides extracting its needs also
contributes something or the other which would be
useful to other organisms.
(1) Species capture and store energy.
(2) These produce and decompose organic material.
(3) These help to cycle water and nutrients throughout the ecosystem.
(4) These fix atmospheric gases and help regulate
climate. These functions are important for ecosystem
function and human survival. The more diverse an
ecosystem is better are the chances for the species to
survive through adversities and attacks and
consequently is more productive. Hence, the loss of
species would decrease the ability of the system to
maintain itself. Just like a species with high genetic
diversity, an ecosystem with high biodiversity may
have a greater chance of adapting to environmental
change. In other words, the more the variety of species
in an ecosystem, the more stable the ecosystem is
likely to be.
2. Economic role of biodiversity. For all
humans, biodiversity is an important resource in their
day to day life. One important part of biodiversity is
‘crop diversity’, which is also called agro-biodiversity.
Biodiversity is seen as a reservoir of resources to be
drawn upon for the manufacturer of food,
pharmaceutical and cosmetic products. This concept
of biological resources is responsible for the
deterioration of biodiversity. At the same time, it is
also the origin of new conflicts dealing with rules of
division and appropriation of natural resources. Some
of the important economic commodities that
biodiversity supplies to humankind are : food crops,
livestock, forestry, fish, medication etc.
3. Scientific role of biodiversity. Biodiversity
is important because each species can give us some
clue as to how life evolved and will continue to evolve.
Biodiversity also helps in understanding how life
functions and the role of each species in sustaining
ecosystems in which we are also a species. This fact
must dawn upon every one of us so that we live and
let other species also live their life.
4. Ethical role of biodiversity. It is our ethical
responsibility to consider that each and every species
along with us have an intrinsic right to exist. Hence,
it is morally wrong to voluntarily cause extinction of
any species. The level of biodiversity is a good
indicator of the state of our relationships with other
living species. In fact, the concept of biodiversity is
an integral part of many human cultures.
Question 12:
What are the major factors that are responsible for the loss of Biodiversity? What steps are needed to prevent them?
Answer:
Loss of Biodiversity
Since last few decades growth in human population
has increased the rate of consumption of the natural
resources. It has accelerated the loss of species and
habitation in different parts of the world. Tropical
regions which occupy only about one fourth of the
total area of the world, contain about three fourth of
the world human population. Over-exploitation of
resources and deforestation have become rampant to
fulfil the needs of large population. As these tropical
rain forests contain fifty per cent of the species on
the earth, destruction of natural habitats have proved
disastrous for the entire biosphere.
(1) Natural calamities. Natural calamities such
as earthquakes, floods, volcanic eruptions, forest fires,
droughts etc., cause damage to flora and fauna of the
earth, bringing change in the biodiversity of respective
affected regions.
(2) Pesticides. Pesticides and other pollutants
such as hydrocarbons and toxic heavy metals destroy
the weak and sensitive species.
(3) Exotic species. Species which are not natural
inhabitants of the local habitat but are introduced
into the system, are called ‘exotic species.’ There are
many examples when a natural biotic community of
the ecosystem suffered extensive damage because of
introduction of exotic species.
(4) Illegal hunting. During last few decades some
animals like tigers, elephants, rhinoceros, crocodiles,
minks and birds are hunted mercilessly by poachers
for their horns, tusks, and hides etc. It has resulted
in certain types of selected group of organisms as
endangered category.
Conservation of Biodiversity
Biodiversity is important for human existence. All
forms of life are so closely interlinked that disturbance
in one gives rise to imbalance in the others. If species
of plants and animals become endangered they cause
degradation in the environment, which may threaten
human’s own existence.
There is an urgent need to educate people to adopt
environment friendly practices and re-orient their