Page 196 - Innovator's Science-8

2. Which of these is an example of geodiversity?
i. A variety of birds chirping in a forest.
ii. Different landforms like mountains, valleys, and deserts.
iii. Changing weather during monsoons.

iv. Number of different types of fish in a pond.
Ans. ii. Different landforms like mountains, valleys, and deserts.
3. If the Earth were smaller with the same density, what might happen to its atmosphere?
i. It would become thicker and ho er.
ii. It would escape into space due to weaker gravity.
iii. It would become frozen.

iv. It would cause stronger winds.
Ans. ii. It would escape into space due to weaker gravity.
4. In sexual reproduc on, why are offspring different from their parents?
i. They grow in different climates.

ii. They eat different food.
iii. They acquire new instruc ons a er birth.
iv. They get mixed instruc ons (genes) from both parents.
Ans. (iv) They get mixed instruc ons (genes) from both parents.
5. You no ce ny green plants growing in cracks on your school wall a er the monsoon. Where do you
think the seeds came from? What condi ons helped these plants grow there?
Ans. Seeds likely came from nearby plants carried by wind, birds, or insects. For example, birds ea ng fruit
may have dropped or passed seeds into the crack in the wall. The monsoon rains provided water, which
is essen al for seeds to start growing. The crack in the wall trapped some soil or organic material, giving
nutrients to the seed. Sunlight and air outside help the plant perform photosynthesis and breathe. This
small, moist crack created a ny safe place, called a microhabitat, that allowed the seed to grow even in
an unusual spot like a wall crack.
6. A city has recently cut down a large patch of forest to build new roads and buildings. Discuss the
possible effects this could have on the local climate and biodiversity. How might this affect water
availability or quality in the area?
Ans. Deforesta on has big effects on the local climate and biodiversity. When trees are cut down, fewer trees
are le to absorb carbon dioxide, a greenhouse gas, which can make local temperatures rise because
there is less shade and less balance in greenhouse gases. Trees also help with rainfall by releasing water
vapor into the air, so cu ng them down can disturb rainfall pa erns and make the area drier. For
biodiversity, losing forests means many plants and animals lose their homes and food sources. Animals
like deer and gers may find it harder to survive, which disrupts the whole ecosystem. Addi onally,
deforesta on affects the water cycle by reducing soil moisture and rainfall while increasing soil erosion;
this soil erosion can pollute nearby water bodies and harm water quality.
7. A friend says, “The Earth has always had climate changes in the past, so today’s global warming is
nothing new.” How would you respond using what you’ve learnt in this and other chapters of your
science book?
Ans. Today’s global warming is different from past natural climate changes because it is mainly caused by
human ac vi es. While nature has caused climate shi s before—for example, ice ages caused by changes

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