Science Worksheet - Grade 9
Board: ACARA
Topic(s): CARBON CYCLE
Total Marks: 20
Time: 20 minutes
Name: ____________________
Class: _______
Date: ___________
INSTRUCTIONS
Choose the best option for each MCQ
Answer all questions
Write neatly and legibly
Multiple Choice Questions
What is the primary form of carbon found in the Earth’s atmosphere?
a) Carbon monoxide
b) Carbon dioxide
c) Methane
d) Carbonic acid
Which process removes carbon dioxide from the atmosphere?
a) Respiration
b) Combustion
c) Photosynthesis
d) Decomposition
How do animals obtain carbon?
a) By breathing it in from the atmosphere
b) By absorbing it through their skin
c) By consuming plants or other animals
d) By drinking water containing dissolved carbon
What is the main role of decomposers in the carbon cycle?
a) To produce carbon dioxide through photosynthesis
b) To convert atmospheric carbon into fossil fuels
c) To break down dead organic matter, returning carbon to the soil and atmosphere
d) To store carbon in their bodies indefinitely
Which human activity significantly increases the amount of carbon dioxide in the atmosphere?
a) Planting trees
b) Using solar energy
c) Burning fossil fuels
d) Recycling waste
Carbon is an essential element for all ____________________.
a) Rocks
b) Living organisms
c) Oceans
d) Minerals
The process of burning organic matter, which releases carbon dioxide, is called ____________________.
a) Photosynthesis
b) Respiration
c) Decomposition
d) Combustion
Where is a large amount of carbon stored for long periods on Earth?
a) In the air
b) In clouds
c) In fossil fuels and oceans
d) In active volcanoes
What do plants use atmospheric carbon dioxide for?
a) To release oxygen
b) To make their own food
c) To absorb water
d) To cool down
Which of the following is a fossil fuel?
a) Wood
b) Coal
c) Water
d) Air
Carbon dioxide dissolves in ____________________ to form carbonic acid, affecting marine life.
a) Soil
b) Air
c) Oceans
d) Rocks
When organisms die, their carbon can be returned to the soil by the process of ____________________.
a) Evaporation
b) Condensation
c) Decomposition
d) Precipitation
The carbon cycle describes the movement of carbon between the atmosphere, oceans, land, and ____________________.
a) Outer space
b) The Earth’s core
c) Living organisms
d) The moon
What is the chemical symbol for carbon?
a) Ca
b) Co
c) C
d) Cr
Which gas is a major greenhouse gas and contains carbon?
a) Oxygen
b) Nitrogen
c) Carbon dioxide
d) Hydrogen
What is the primary source of carbon for plants?
a) Carbon from the soil
b) Carbon from water
c) Carbon dioxide from the atmosphere
d) Carbon from other plants
Which process releases carbon dioxide into the atmosphere from living organisms?
a) Photosynthesis
b) Transpiration
c) Respiration
d) Germination
Carbon can be stored in the Earth’s crust over millions of years in the form of ____________________.
a) Water vapor
b) Atmospheric gases
c) Fossil fuels
d) Clouds
Which of these is NOT typically considered a carbon sink?
a) Forests
b) Oceans
c) Fossil fuel combustion
d) Soil
What is the role of photosynthesis in the carbon cycle?
a) It releases carbon dioxide into the atmosphere.
b) It converts carbon dioxide into organic compounds.
c) It breaks down organic compounds to release carbon.
d) It stores carbon in the Earth’s crust.