Two Marks Questions with Answers

Two Marks Questions with Answers

 

Q.1 Define ecology or environment.

Ans. : The environment is defined as, “the whole physical and biological system in which man and other organisms live". Environmental studies involve every issue that affects living organisms.

 

Q.2 Explain in brief biotic and abiotic components of ecosystem.

Ans. :          .

• The structure of an ecosystem indicates it’s components (species diversity) and their interdependency for growth and survival.

• An ecosystem has two types of components.

1. Abiotic component (non-living).

2. Biotic component (living).

1. Abiotic (Non-Living) Components

• The abiotic components determine the type of organisms can live in specific area. Abiotic components can be physical components or chemical components.

• Physical components usually include sunlight, water, soil, temperature etc. These are necessary growth of species.

• Chemical components provide necessary nutrients to the organism. It includes Carbohydrates, proteins, liquids, nitrogen, phosphorous, potassium

2. Biotic Components

• Biotic components are living organisms of the ecosystem. Biotic component includes- plants, animals, fungi, bacteria and there living organisms.

• The biotic components of an ecosystems can be categorized into three categories, these are :

a) Producers or autotrophs.

b) Consumers or heterotrophs.

c) Decomposers or detrivores.

 

Q.3 Define ecosystem. State the characteristics of an ecosystem.

Ans. : Ecosystem : An ecosystem is a community of different species interacting with each other and with non-living environment, exchanging energy to form a stable self supporting system.

Characteristics of an ecosystem

1. It is structural and functional unit of ecology.

2. Its structure is related to species diversity i.e. more complex ecosystem have high species diversity and simple ecosystem have low diversity.

3. Functions of ecosystem are related to energy flow and cycling of material involved and within ecosystem.

4. Ecosystem mature as we pass from less complex to more complex structure i.e. early stage has excess potential energy and relatively high energy flow per unit biomass than later stages.

 

Q.4 Define natural resources and energy resources.

Ans.: Natural Resources -

• The natural resources are defined as the variety of things, processes obtained from environment to satisfy human needs and wants.

Energy Resources -

• Energy sources are available in different forms such as -wood, solar, wind, coal, petroleum, natural gas, nuclear fuels.

 

Q.5 Explain the types of natural energy resources.

Ans. : The natural resources can be classified into two major categories.

1. Renewable resources.

2. Non-renewable resources. 

1. Natural resources : The renewable resources are the resources which regenerates through natural processes within a reasonable time period. They have the potential to regenerate as long as it is not used up faster than it is replaced. Examples : Forests, grass lands, wild life, soil, water, air.

2. Non-renewable resources : Non-renewable resources are not capable of regenerating. These resources have fixed quantity of stock in the earth's crust. These exhaustible resources include - coal, oil, natural gas, iron, copper.

 

Q.6 Mention the Ex-situ measures of conversion of biodiversity.

Ans.: Ex-situ measures for biodiversity -

• Ex-situ ('off site', 'out of place') conservation is a set of conservation techniques involving the transfer of a target species away from its native habitat to a place of safety, such as a zoological garden, botanical garden or seed bank.

• Various Ex-situ measures are :

1. Seed Banks; gene banks

2. Long term captive breeding

3. Animal translocations        

4. Tissue culture banks

5. Cryopreservation of Gametes and Embryos

6. Botanical gardens

7. Zoological gardens

 

Q.7 What is food chain ?

Ans. : Transfer of energy from the source in plants through series of organisms with repeated stages of eating and being eaten is known as food chain.

 

Q.8 Define ecology and ecosystem.

Ans. : Ecology is study of earth's household including plants, animals micro-organisms and people which live together as interdependent.

Ecosystem is a community of different species interacting with each other, exchanging energy to form a stable self supporting system.

 

Q.9 Define biodiversity.

OR What is biodiversity ?

Ans. : Biodiversity is defined as variety and variability of living organisms in a given assemblage.

 

Q.10 What are endangered species ? Give example.  

AU : Dec.-14

Ans. : When number of species of a particular type is reduced to a critical level, it is said to be endangered.

For example - Tiger, Elephant, Sandlewood trees.

 

Q.11 Write the classification of biodiversity.

Ans. : Classification of biodiversity :

1. Genetic diversity

2. Species diversity

3. Ecosystem diversity  

 

Q.12 List out the types of land pollution.

Ans. : Types of land pollution :

1. Solid wast 2. Pesticides and fertilizers

3. Chemicals 4. Deforestation

 

Q.13 Define ecosystem diversity.    

AU : Dec.-16

Ans.: Ecosystem diversity

• Ecosystem diversity is a term that incorporates both habitat and community diversity. A habitat is the environment in which an organism or species lives and includes the physical characteristics (e.g. climate or the availability of suitable food and shelter) that make it especially well suited to meet the life cycle needs of that species.

• A community consists of the assemblage of populations of plants and animals that occupy an area and their interactions with each other and their environment.

• An ecosystem is a unique combination of plant, animal and microorganism communities and their non-living physical characteristics interacting as a functional unit.

• Inherent in ecosystem diversity are thus both biotic (living) and abiotic (non-living) components, which makes it different from both genetic and species diversity.

 

Q.14 What do you understand by species biodiversities ? Give one example.

AU : May-17

Ans. : Species diversity is the number of different species of living things within an area. Species are regarded as populations within which gene flow occurs under natural conditions. Members of one species, do not breed freely with members of other species.

Example : Tiger, lion, teakwood, human being etc.