Oceans & Continents — fully solved
Every in-text “Let’s Explore” activity and every end-of-chapter exercise from the chapter, answered clearly and in full — with the chapter’s own maps and diagrams alongside each solution.
In-Text Questions
The “Let’s Explore” and “Think About It” boxes woven through the chapter — answered in the order they appear.
1What are the circular lines in each map called? And the lines radiating out of the two poles? (Hint: studied in the previous chapter.)
The circular lines running parallel to one another (like rings) are lines of latitude. The lines radiating outward from each pole, running from pole to pole, are lines of longitude.
2Which hemisphere holds more water?
The Southern Hemisphere holds more water. In Fig. 2.2, the map centred on the South Pole (right) is almost entirely blue, with only Antarctica and a few land-tips visible, while the map centred on the North Pole (left) is crowded with large landmasses — North America, Europe and Asia — around the Arctic Ocean.
3What could be the approximate proportion of water to land in the Northern Hemisphere? And in the Southern Hemisphere?
Roughly:
- Northern Hemisphere: about 60% water to 40% land
- Southern Hemisphere: about 80–90% water to 10–20% land
This is a group-discussion estimate — students are expected to judge the proportion by looking at the maps, not recall an exact figure.
4Are all the oceans connected with one another, or are there separations between them?
All the oceans are connected — together they form one continuous body of water. The five ocean names and the lines dividing them on maps are just conventions for convenience; the natural world does not follow these boundaries, and seawater flows freely across all of them.
1If there is such abundance of water on the planet, why is there so much talk of ‘water scarcity’ or a ‘water crisis’?
Because almost all of that abundant water is seawater — salty and unfit for drinking, farming, or most everyday uses. Freshwater makes up only a very small share of the planet’s water, and most of it is locked away in glaciers, ice, and deep groundwater, or is far from where people live. The small portion that is actually usable (rivers, lakes, accessible groundwater) is also being over-used and polluted, which is why regions face water scarcity despite the ocean’s vastness.
2What ways of saving water are you aware of? Which ones have you seen practised at home, at your school, and in your village, town or city?
Some common water-saving practices:
- Turning off the tap while brushing teeth or soaping hands
- Fixing leaking taps and pipes promptly
- Using a bucket instead of a running hose or shower
- Rainwater harvesting on rooftops
- Reusing household water (e.g., for watering plants)
- Drip irrigation instead of flooding fields, in farms
- Installing water-efficient taps and fixtures in schools and homes
(This is a reflective, open-ended question — describe what you have actually noticed being practised around you.)
1Locate the five oceans and mark the hemisphere(s) they belong to.
| Ocean | Northern Hemisphere | Southern Hemisphere |
|---|---|---|
| Pacific Ocean | ✓ | ✓ |
| Atlantic Ocean | ✓ | ✓ |
| Indian Ocean | ✓ (small part) | ✓ (mostly) |
| Southern Ocean | ✗ | ✓ |
| Arctic Ocean | ✓ | ✗ |
The Pacific and Atlantic Oceans stretch across both hemispheres. The Indian Ocean lies mostly in the Southern Hemisphere, with only a small part crossing north of the equator. The Southern Ocean lies entirely around Antarctica in the south, while the Arctic Ocean lies entirely around the North Pole.
1Counting the number of squares, name the largest continent and the smallest.
The continent with the most squares is Asia — the largest continent. The one with the fewest squares is Australia — the smallest continent. This matches the real world: Asia covers about 44.5 million km², while Australia covers only about 7.7 million km².
2Which one is larger — North America or South America? Africa or North America? Antarctica or Australia?
- North America is larger than South America
- Africa is larger than North America
- Antarctica is larger than Australia
3Re-colour the diagram with a single colour for Europe and Asia, and rename the result ‘Eurasia’. Compare its size with South America’s.
Once Europe and Asia are coloured as a single block and renamed ‘Eurasia’, it becomes by far the largest landmass in the diagram — combining roughly 44.5 million km² (Asia) with about 10.2 million km² (Europe), giving nearly 54.7 million km² in all. That makes Eurasia about three times the size of South America (≈17.8 million km²).
4Write down the list of continents from the smallest to the largest.
Australia → Europe → Antarctica → South America → North America → Africa → Asia
Exercise Questions
“Questions, activities and projects” — page 39–40 of the chapter.
Explain the following terms:
A continent is a large, continuous expanse of land on the Earth’s surface. Continents are also surrounded by water, but because of their huge size they are not called islands. Depending on how they are counted, there can be 4 to 7 continents — the most widely used count is seven: Asia, Africa, North America, South America, Antarctica, Europe and Australia.
An ocean is one of the largest water bodies on the globe. Oceans together hold most of the water on the planet. There are five oceans — the Pacific, Atlantic, Indian, Arctic and Southern (Antarctic) Ocean — and although given separate names, they are all interconnected; the boundaries between them are only conventions.
An island is a (comparatively small) piece of land completely surrounded by water on all sides. Continents are not counted as islands only because of their enormous size. Greenland is the largest island in the world; India itself has more than 1,300 islands, including the Andaman & Nicobar Islands and the Lakshadweep Islands.
Let us draw — Without looking at the maps in this chapter, draw the continents free hand on a sheet of paper and colour them. Then compare your drawing with the map of oceans and continents in the chapter.
This is a hands-on drawing activity with no single fixed answer — you draw it yourself, then check it against Fig. 2.3 below. A few landmark shapes make the comparison easier:
- Africa — wide near the top, narrowing to a point in the south
- Asia — the biggest, bulkiest shape, joined to Europe on its west
- North America — wide at the top, tapering down, joined to South America by a narrow strip (Central America)
- South America — a long, narrow triangle pointing south
- Australia — a compact, roughly oval/rectangular island continent
- Antarctica — a broad, roughly circular ice-covered mass at the very bottom
- Europe — small and deeply indented with coastlines, attached to Asia’s west
Draw the equator as a light guide-line first — it helps you judge how far each continent sits above or below it, which makes the proportions come out much more accurately.
Let us do — On the outline map of the world given below, label all the continents and oceans.
Use this fully-labelled version of the map to check your work:
- Continents: North America, South America, Europe, Asia, Africa, Australia, Antarctica
- Oceans: Pacific Ocean (appears on both left and right edges), Atlantic Ocean, Indian Ocean, Arctic Ocean, Southern Ocean
Solve this crossword
Across
Down
Note: 6-Across is EURASIA because India is part of Asia, and geologists regard Europe and Asia together as a single continent called Eurasia (see page 35 of the chapter) — this is also the answer whose 7 letters fit the grid.