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NCERT Solutions for Class 12 Biology Chapter 15
Biodiversity and Conservation Class 12
Chapter 15 Biodiversity and Conservation Exercise Solutions
Exercise : Solutions of Questions on Page Number : 268
Q1 :
Name the three important components of biodiversity.
Answer :
Biodiversity is the variety of living forms present in various ecosystems. It includes variability among life forms from all
sources including land, air, and water. Three important components of biodiversity are:
(a) Genetic diversity
(b) Species diversity
(c) Ecosystem diversity
Q2 :
How do ecologists estimate the total number of species present in the world?
Answer :
The diversity of living organisms present on the Earth is very vast. According to an estimate by researchers, it is
about seven millions.
The total number of species present in the world is calculated by ecologists by statistical comparison between a
species richness of a well studied group of insects of temperate and tropical regions. Then, these ratios are
extrapolated with other groups of plants and animals to calculate the total species richness present on the Earth.
Q3 :
Give three hypotheses for explaining why tropics show greatest levels of species richness.
Answer :
There are three different hypotheses proposed by scientists for explaining species richness in the tropics.
(1) Tropical latitudes receive more solar energy than temperate regions, which leads to high productivity and high
species diversity.
(2) Tropical regions have less seasonal variations and have a more or less constant environment. This promotes the
niche specialization and thus, high species richness.
www.ncrtsolutions.in
NCERT Solutions for Class 12 Biology Chapter 15
Biodiversity and Conservation Class 12
Chapter 15 Biodiversity and Conservation Exercise Solutions
Exercise : Solutions of Questions on Page Number : 268
Q1 :
Name the three important components of biodiversity.
Answer :
Biodiversity is the variety of living forms present in various ecosystems. It includes variability among life forms from all
sources including land, air, and water. Three important components of biodiversity are:
(a) Genetic diversity
(b) Species diversity
(c) Ecosystem diversity
Q2 :
How do ecologists estimate the total number of species present in the world?
Answer :
The diversity of living organisms present on the Earth is very vast. According to an estimate by researchers, it is
about seven millions.
The total number of species present in the world is calculated by ecologists by statistical comparison between a
species richness of a well studied group of insects of temperate and tropical regions. Then, these ratios are
extrapolated with other groups of plants and animals to calculate the total species richness present on the Earth.
Q3 :
Give three hypotheses for explaining why tropics show greatest levels of species richness.
Answer :
There are three different hypotheses proposed by scientists for explaining species richness in the tropics.
(1) Tropical latitudes receive more solar energy than temperate regions, which leads to high productivity and high
species diversity.
(2) Tropical regions have less seasonal variations and have a more or less constant environment. This promotes the
niche specialization and thus, high species richness.
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