For each idea: show it, ask before you tell, then say one line.
Gather a potted plant, paper, a pencil, vegetable peels, clean plastic packaging, a used glass jar and fallen leaves beneath a shrub.
Common misconceptions & worked visual for this chapter · 15 practice questions with answers
Living things interact with each other and their non-living surroundings.
Producers make food, consumers eat organisms, and decomposers break remains down.
Linked feeding chains form a web.
About one-tenth of feeding-level energy reaches the next level.
Some lasting chemicals become more concentrated at higher feeding levels.
Ozone high in the atmosphere absorbs harmful ultraviolet radiation.
Chlorofluorocarbons (CFCs) release chlorine high above Earth, causing ozone loss.
Separate waste by how it breaks down or can be recovered.
A real problem
Its waste-management transformation began in 2015, after overflowing bins and roadside dumping littered the city.
Residents began separating their household garbage.
Separated organic waste was made into compost.
NITI Aayog reported that Ambikapur became free of garbage dumping sites.
Concept Lab · Common misconception
Wrong
Top predators receive the most energy because they eat other animals.
Why it feels right. I focus on the size or number of prey.
Right
Energy available to a trophic level is a fraction of the energy at the level below.
Worked example
With an illustrative 10% transfer, 1,000 energy units in producers support about 100 in primary consumers and 10 in secondary consumers.
One per step. The answer and the reason are given.
Does sunlight belong in this garden ecosystem?
Yes. Plants depend on this non-living part of the ecosystem.
What happens to dead remains if decomposers stop working?
They pile up. Decomposers break remains down and release nutrients.
Which way should the arrow between grass and a grass-eating insect point?
From grass to insect. The insect receives food and energy from the grass.
If one feeding level has 500 J, about how much reaches the next?
About 50 J. Only about one-tenth transfers to the next feeding level.
Why does retained pesticide become more concentrated from plants to predatory fish?
Repeated meals add retained pesticide. Predators eat many contaminated organisms and keep pesticide that their bodies cannot easily remove.
Which radiation does high-altitude ozone absorb to protect skin?
Ultraviolet radiation. Ozone absorbs harmful UV, reducing the radiation reaching living things.
What effect do released CFCs have on ozone high in the atmosphere?
Its amount decreases. Chlorine released from CFCs destroys ozone, allowing more harmful UV through.
Where should plastic packaging go when peels are collected for compost?
Apart from the peels. Plastic does not biodegrade with food waste and needs separate handling.
