Bio Geo Chemical Cycles AP 9th Class Biology Bits 11th Lesson 

Bio Geo Chemical Cycles

AP 9th Class Biology Bits 11th Lesson

1. Choose the correct answers :

Question 1.
The flow of nutrients from living organisms to environment and from environment to living organisms occur through
A) Biogeochemical cycles
B) Biocycles
C) Chemical cycles
D) Geocycles
Answer:
A) Biogeochemical cycles

Question 2.
The percentage of salt water on earth is
A) 3%
B) 1%
C) 97%
D) 2%
Answer:
C) 97%

Question 3.
The human body is composed of about how much water ?
A) 80%
B) 70%
C) 90%
D) 10%
Answer:
B) 70%

Question 4.
These form integral part of basic organic compounds of life.
A) Nitrogen, hydrogen
B) Hydrogen, phosphorous
C) Hydrogen, oxygen
D) Nitrogen, oxygen
Answer:
C) Hydrogen, oxygen

Question 5.
The element that is abundantly present in atmosphere is
A) Oxygen
B) Hydrogen
C) CO₂
D) Nitrogen
Answer:
D) Nitrogen

Question 6.
The free living bacteria that fixes nitrogen is
A) Nitrosomonas
B) Rhizobium
C) Nitrobacter
D) All
Answer:
A) Nitrosomonas

Question 7.
Nitrogen makes its way back into the atmosphere through a process called
A) Ammonification
B) Denitrification
C) Assimilation
D) Nitrification
Answer:
B) Denitrification

Question 8.
The excessive amount of nitrates and other nitrogenous compounds when they reach rivers and lakes cause too much growth of
A) Bryophytes
B) Fungi
C) Algae
D) Pteridophytes
Answer:
C) Algae

Question 9.
It is reponsible for maintaining the earth as a green – house with temperature conditions suitable for life ?
A) Oxygen
B) CO₂
C) Hydrogen
D) Nitrogen
Answer:
B) CO₂

Question 10.
The main reservoirs of carbon are
A) Sedimentary rocks
B) Fossil fuels
C) Oceans
D) All the above
Answer:
D) All the above

Question 11.
Excessive amount of carbon dioxide and other green house gases has been emitted to the environment due to
A) Burning of fossil fuels, deforestation
B) Burning of fossil fuels, industrialization
C) Deforestation, industrialization
D) Burning of fossil fuels, deforestation, industrialization
Answer:
D) Burning of fossil fuels, deforestation, industrialization

Question 12.
These are poisoned by elemental oxygen
A) Algae
B) Virus
C) Bacteria
D) All the above
Answer:
C) Bacteria

Question 13.
Decomposition of organic waste requires
A) Hydrogen
B) Oxygen
C) Nitrogen
D) Phosphorous
Answer:
B) Oxygen

Question 14.
The layer extends from the earth’s surface up to about 10 kilometers in altitude is
A) Stratosphere
B) Ionosphere
C) Mesosphere
D) Troposphere
Answer:
D) Troposphere

Question 15.
The number of oxygen atoms present in ozone is
A) 2
B) 3
C) 4
D) 5
Answer:
B) 3

Question 16.
Ozone layer absorbs these radiations of sun
A) Infrared rays
B) Ultraviolet rays
C) Cosmic rays
D) Gamma rays
Answer:
B) Ultraviolet rays

Question 17.
These are responsible for destruction of ozone layer
A) Pepticides
B) CO₂
C) Chlorofluoro carbons
D) Hydrogen
Answer:
C) Chlorofluoro carbons

Question 18.
To protect ozone layer, the protocol emerged was
A) Washington protocol
B) Montreal protocol
C) Vancover protocol
D) Geneva protocol
Answer:
B) Montreal protocol

Question 19.
The element present in diamond is
A) Carbon
B) Nitrogen
C) Hydrogen
D) Phosphorous
Answer:
A) Carbon

Question 20.
Which of the following organisms is a free living nitrogen fixer ?
A) Rhizobium
B) Nitrosomonas
C) Mycorrhiza
D) None
Answer:
B) Nitrosomonas

Question 21.
Which of the following is the elemental form of carbon ?
A) Graphite
B) Diamond
C) Soot
D) All the above
Answer:
D) All the above

Question 22.
The elements that is common among proteins, DNA, RNA and Alkaloids ………………….
A) Carbon
B) Nitrogen
C) Sulphur
D) Mercury
Answer:
B) Nitrogen

Question 23.
The colour of ozone is ……………….
A) Green
B) Blue
C) Yellow
D) Pink
Answer:
B) Blue

Question 24.
Which of the following is not a green house gas ?
A) CO₂
B) CO
C) CH₄
D) C₆H₆
Answer:
D) C₆H₆

Question 25.
The percentage of CO₂ in the atmosphere is
A) 0.04%
B) 0.4%
C) 0.08%
D) None of the above
Answer:
A) 0.04%

Question 26.
Oxygen is returned to the atmosphere mainly by
A) Respiration
B) Photosynthesis
C) Burning of wood
D) Fungi
Answer:
B) Photosynthesis

Question 27.
Ozone layer is getting depleted because of …………………
A) Automobiles
B) Industrial units
C) Compounds of flourine and chlorine
D) None
Answer:
C) Compounds of flourine and chlorine

Question 28.
Which of the following is a green house gas ?
A) CO₂
B) CFCs
C) CH₄
D) All
Answer:
D)All

Question 29.
Montreal protocol substances on
A) Ozone depletion
B) Green house effect
C) Air pollution
D) Water pollution
Answer:
A) Ozone depletion

Question 30.
The main source of CFCs …………………
A) Refrigerators
B) Air conditioners
C) Jet Flights
D) All the above
Answer:
D) All the above

Question 31.
Montreal protocol signed by 24 countries in the year ………………….
A) 1985
B) 1984
C) 1987
D) 1990
Answer:
C) 1987

Question 32.
Copenhagen meeting on revise of montreal protocol was held in the year ……………….
A) 1994
B) 1992
C) 1995
D) 1996
Answer:
B) 1992

Question 33.
Direct exposure of U.V radiation causes
A) Skin cancer
B) Destroys marine life
C) Damage to crops
D) All the above
Answer:
D) All the above

Question 34.
The ozone hole is observed here
A) Pacific ocean
B) Indian ocean
C) Antarctica region
D) Arctic region
Answer:
C) Antarctica region

Question 35.
These crops increase soil fertility
A) Food
B) Commercial
C) Legume
D) Vegetable
Answer:
C) Legume

Question 36.
Symbiotic bacteria that fixes the nitrogen is …………………..
A) Nitrosomonas
B) Nitrobactor
C) Micorrhiza
D) Rhizobium
Answer:
D) Rhizobium

Question 37.
Carbon burried under the ocean floor might take this much of time to return to the atmosphere
A) 12 million
B) 14 Million
C) 15 million
D) 10 Million
Answer:
D) 10 Million

Question 38.
The atmospheric layer continues from 10 km to about 50 km is ……………….
A) Troposphere
B) Ionosphere
C) Stratosphere
D) None
Answer:
C) Stratosphere

Question 39.
Choose the correct matching from the following.
List – A
1) Nitrogen
2) Oxygen
3) Fresh water

List – B
a) 3% of water on earth
b) 21% in air
c) 78% in air
A) 1 – a, 2 – b, 3 – c
B) 1 – c, 2 – a, 3 – b
C) 1 – c, 2 – b, 3 – a
D) 1 – b, 2 – c, 3 – a
Answer:
C) 1 – c, 2 – b, 3 – a

Question 40.
Choose the correct matching from the following.
List – A
1) Nitrosomonas
2) Ozone
3) Green house effect

List – B
a) CO₂ water vapour
b) CFCs
c) Nitrogen fixation
A) 1 – a, 2 – b, 3 – c
B) 1 – b, 2 – a, 3 – c
C) 1 – c,2 – a,3 – b
D) 1 – c,2 – b,3 – a
Answer:
D) 1 – c,2 – b,3 – a

Question 41.
Which of the following is an inert gas ?
A) Nitrogen
B) Oxygen
C) Methane
D) Xenon
Answer:
D) Xenon

Question 42.
Large amount of fresh water is present in
A) Seas
B) Rivers
C) Polar ice caps
D) Lakes
Answer:
C) Polar ice caps

Question 43.
Very few animals and plants are present in deserts. Because
A) There is sand
B) There is very little water
C) There are no roads
D) It is hot in desert
Answer:
B) There is very little water

Question 44.
Hydrological cycle occurs between
A) Land and air
B) Air and sea
C) Land and sea
D) Land, sea and atmosphere
Answer:
D) Land, sea and atmosphere

1. Match the following.

i)

Group – A	Group – B
1) Nitrogen	A) 21% in air
2) Oxygen	B) 97% of water on earth
3) Carbon dioxide	C) 78% in air
4) Fresh water	D) 2% of water on earth
5) Salt water	E) 0.04% in air
	F) 3% of water on earth
	G) 0.05% in air

Answer:
1) Nitrogen – C) 78% in air
2) Oxygen – A) 21% in air
3) Carbon dioxide – E) 0.04% in air
4) Fresh water – F) 3% of water on earth
5) Salt water – B) 97% of water on earth

ii)

Group – A	Group – B
1) Rhizobium	A) NH3
2) Nitrosomonas	B) NO3 to N2
3) Ozone	C) CO2
4) Ammonification	D) Nitrogen fixation
5) Green house effect	E) Chlorofluoro carbons
	F) Methane
	G) Legumes

Answer:
1) Rhizobium – G) Legumes
2) Nitrosomonas – D) Nitrogen fixation
3) Ozone – E) Chlorofluoro carbons
4) Ammonification – A) NH₃
5) Green house effect – C) CO₂

Question 45.
The troposphere extends from earth’s surface to a height of approximately
A) 1000m
B) 8848m
C) 100 km
D) 10 km
Answer:
D) 10 km

Question 46.
Which of the following is NOT an eco – friendly activity ?
A) Growing plants in waste lands
B) Minimizing electricity consumption
C) Using compost in fields
D) Maximising vehicles usage
Answer:
D) Maximising vehicles usage

Question 47.
Montreal protocol focuses on
A) Protect ozone layer
B) Control and phase out of ozone depleting factors
C) Control and phase out CFC and halocarbons
D) All of these
Answer:
D) All of these

Question 48.
Production of (X) from (Y) and other (Z) is called Ammonification. Here X, Y, Z respectively are
A) Ammonia, Nitrates and other nitrogenous compounds
B) Urea, Nitrogen and other carbon compounds
C) Nitrates, Ammonia and Nitrites
D) Rhizobium, Azolla, Nostoc
Answer:
A) Ammonia, Nitrates and other nitrogenous compounds

Question 49.
What happens if nitrogen fixation is stopped ?
1) Nitrogen in the soil is reduced
2) Nitrogen will not be available to plant
3) Plant and animal would die
4) Depletion of nitrogen in the environment
A) 1, 2
B) 3, 4
C) 1, 3
D) 1, 4
Answer:
A) 1, 2