BIOLOGY CH24 Environmental Science - Tamil Nadu Board STD 9 Science Questions

Q 1MCQ1 Mark

Increased amount of ______ in the atmosphere, results in greenhouse effect and global warming.

A
carbon monoxide
B
sulphur dioxide
C
nitrogen dioxide
D
carbon dioxide

View full solution →

Q 2MCQ1 Mark

The atmospheric carbon dioxide enters into the plants through the process of ______.

A
photosynthesis
B
assimilation
C
respiration
D
decomposition

View full solution →

Q 3MCQ1 Mark

The ice sheets from the north and south poles and the icecaps on the mountains, get converted into water vapour through the process of ______.

A
evaporation
B
condensation
C
sublimation
D
infiltration

View full solution →

Q 4MCQ1 Mark

All the factors of biosphere which affect the ability of organisms to survive and reproduce are called as ______.

A
biological factors
B
abiotic factors
C
biotic factors
D
physical factors

View full solution →

Q 5MCQ1 Mark

India accounts for …………………% of all recorded species.

A
2-4%
B
5-6%
C
6-7%
D
7-8%

View full solution →

Q 6Assertion (A) & Reason (B) MCQ1 Mark

Assertion (A) : The moist skin in earthworm helps in oxygenation of blood.
Reason (R) : The slippery skin of earthworm is kept moist.

A
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
✓
If both assertion and reason are true but reason is not the correct explanation of assertion.
C
If assertion is true but reason is false
D
If assertion is false but reason is true.

Answer: B.

View full solution →

Q 7Assertion (A) & Reason (B) MCQ1 Mark

Assertion (A) : By increasing the amount of carbon dioxide, earth becomes warmer.
Reason (R) : Carbon dioxide is a green house gas.

✓
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B
If both assertion and reason are true but reason is not the correct explanation of assertion.
C
If assertion is true but reason is false
D
If assertion is false but reason is true.

Answer: A.

View full solution →

Q 8Assertion (A) & Reason (B) MCQ1 Mark

Assertion (A) : Plants and animals can utilize atmospheric nitrogen.
Reason (R) : Atmosphere is a rich source of nitrogen.

A
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B
If both assertion and reason are true but reason is not the correct explanation of assertion.
C
If assertion is true but reason is false
✓
If assertion is false but reason is true.

Answer: D.

View full solution →

Q 9Assertion (A) & Reason (B) MCQ1 Mark

Assertion (A) : Infiltration and Percolation are two related but different processes.
Reason (R) : They describe the movement of water through atmosphere.

A
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B
If both assertion and reason are true but reason is not the correct explanation of assertion.
✓
If assertion is true but reason is false
D
If assertion is false but reason is true.

Answer: C.

View full solution →

Q 10Assertion (A) & Reason (B) MCQ1 Mark

Assertion (A) : Biosphere is a dynamic and stable system.
Reason (R) : There is a constant interaction between biotic and abiotic components in the biosphere.

✓
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B
If both assertion and reason are true but reason is not the correct explanation of assertion.
C
If assertion is true but reason is false
D
If assertion is false but reason is true.

Answer: A.

View full solution →

Q 11[2 Mark Questions]2 Marks

How does a bat adapt itself to its habitat?

View full solution →

Q 12[2 Mark Questions]2 Marks

Explain carbon cycle with the help of a flow chart.

View full solution →

Q 13[2 Mark Questions]2 Marks

List some of the ways in which you could save water in your home and school.

View full solution →

Q 14[2 Mark Questions]2 Marks

Why is it important to conserve water?

View full solution →

Q 15[2 Mark Questions]2 Marks

What are the challenges faced by hydrophytes in their habitat?

View full solution →

Q 16Match The Following.4 Marks

Match the following.

Microorganism	Role Played
Nitrosomonas	Nitrogen fixation
Azotobacter	Ammonification
Pseudomonas species	Nitrification
Putrefying bacteria	Denitrification