Question
The graph illustrates the relationship between atmospheric carbon dioxide levels and global temperature anomalies (deviations from average global temperatures) from the Industrial Revolution through to 2017.
Which statement explains the correlation between atmospheric carbon dioxide concentration and temperature shown in the graph?
A. Carbon dioxide heats up the surface of the Earth.
B. More short wave radiation bounces back to space, causing warmer seasons.
C. Less long wave radiation can escape the atmosphere, heating up the Earth.
D. Less radiation is emitted by the Earth’s surface, increasing seasonal fluctuations.
▶️Answer/Explanation
Ans. C
less long wave radiation escaping the atmosphere can heat up the Earth:
Greenhouse effect
Greenhouse gases, like water vapor and carbon dioxide, allow short-wavelength radiation from the sun to pass through the Earth’s atmosphere, but absorb and re-radiate long-wavelength radiation back to Earth’s surface. This process is called the greenhouse effect and keeps the Earth warm enough to support life.
Warming the lower atmosphere
Radiation from the warmed upper atmosphere and a small amount from the Earth’s surface radiates out to space, warming the lower atmosphere and the planet’s surface.
Question
The diagram shows flows of energy and matter in an ecosystem. What do the letters P, Q and R represent?
▶️Answer/Explanation
Ans. C
Question
The three-toed sloth, Bradypus variegatus, lives in tree tops where it feeds on leaves. It also feeds on algae and fungi which live in its fur.
In which trophic group should the three-toed sloth be classified?
A. Autotroph
B. Consumer
C. Detritivore
D. Saprotroph
▶️Answer/Explanation
Markscheme
B
Question
Which processes occur in an ecosystem?
I. Biomass increases in each successive trophic level.
II. Inorganic nutrients are recycled.
III. Chemical energy is stored in carbon compounds.
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
▶️Answer/Explanation
Markscheme
C
Question
A hummingbird is shown visiting a large flower.
What makes this a mutualistic relationship?
A. The bird feeds on nectar and transfers pollen to the stamen of a flower of the same species.
B. The bird obtains nutrients and the plant is assisted with pollination for sexual reproduction.
C. The bird requires pollen as a protein source and, while obtaining this, disperses seeds for the plant.
D. The bird transfers pollen to the stigma of flowers of a different species while feeding.
Answer/Explanation
Ans:B
Question
Hummingbirds eat flower nectar and small insects. To which nutritional group do they belong?
Autotrophs
Consumers
Detritivores
Saprotrophs
Answer/Explanation
Ans: B