(i) The Coastal Plains are located along the ____________.
Ans: coastlines of oceans and seas
Coastal plains are low-lying, relatively flat areas of land that run along the edges of oceans, seas, or large bodies of water. They are often formed by the deposition of sediments brought by rivers or by the gradual rise of sea levels over time.
(ii) Islands are usually surrounded by ____________.
Ans: water
An island is a piece of land that is completely surrounded by water. This water can be in the form of oceans, seas, rivers, or lakes, depending on the type of island.
(iii) The area where land meets the sea is called the ____________.
Ans: coast
The coast is the boundary or interface between the landmass and the sea or ocean. It is a dynamic and ecologically diverse environment where various natural processes and ecosystems interact.
(iv) The ____________ is the largest ocean in the world.
Ans: Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's oceans, covering a vast expanse of the planet's surface. It is known for its enormous size and wide-ranging influence on global climate patterns.
(v) ____________ is the process of moving sand from one place to another along the coast.
Ans: Beach drift
Beach drift refers to the lateral movement of sand particles along a beach due to the action of waves and currents. It plays a crucial role in shaping the appearance and features of coastal areas.
(i) Which of the following is NOT a feature of coastal plains?
(a) Hills
(b) Mountains
(c) Valleys
(d) Plateaus
Ans: (b)
Coastal plains are characterized by flat land and gentle slopes, not mountains.
(ii) What surrounds an island?
(a) Desert
(b) River
(c) Water
(d) Forest
Ans: (c)
Islands are landmasses completely surrounded by water.
(iii) Which ocean is known for being the smallest?
(a) Pacific Ocean
(b) Atlantic Ocean
(c) Indian Ocean
(d) Arctic Ocean
Ans: (d)
The Arctic Ocean is the smallest among the world's oceans.
(iv) What causes tides in the oceans?
(a) Wind
(b) Moon's gravitational pull
(c) Earth's rotation
(d) Volcanic activity
Ans: (b)
The gravitational pull of the moon causes ocean tides.
(v) Coastal erosion can be caused by ____________.
(a) Planting trees
(b) Building sandcastles
(c) Ocean currents and waves
(d) Collecting seashells
Ans: (c)
Ocean currents and waves contribute to coastal erosion by wearing away the land.
(i) Coastal plains are found only along the oceans.
Ans: False
Coastal plains can also be found along lakes and seas, not just oceans.
(ii) Islands are always large landmasses surrounded by water.
Ans: False
Islands can vary in size and can be small or large landmasses surrounded by water.
(iii) The Pacific Ocean is the smallest ocean on Earth.
Ans: False
The Pacific Ocean is the largest ocean on Earth.
(iv) Tides are primarily caused by the moon's gravitational pull.
Ans: True
Tides are primarily caused by the gravitational pull of the moon.
(v) Coastal erosion is the process of adding more sand to the beach.
Ans: False
Coastal erosion is the process of land being gradually worn away by natural forces.
(vi) The coastline never changes over time.
Ans: False
Coastlines change due to erosion, deposition, and other natural processes.
(vii) Islands can be formed by volcanic activity.
Ans: True
Volcanic activity can lead to the formation of islands.
(viii) Coastal areas have a mild climate due to the constant ocean breeze.
Ans: False
Coastal areas can have diverse climates influenced by various factors.
(ix) The Great Barrier Reef is the largest coral reef in the world.
Ans: True
The Great Barrier Reef is indeed the largest coral reef system globally.
(x) Mangrove trees help prevent soil erosion along the coasts.
Ans: True
Mangrove trees have root systems that help stabilize coastal soil and prevent erosion.
Ans:
(i) Coastal Plains: Coastal plains are flat areas of land that lie along coastlines and are usually formed by the deposition of sediments from rivers and oceans.
(ii) Tides: Tides are the regular rising and falling of ocean waters caused by the gravitational pull of the moon and the sun on Earth's oceans.
(iii) Island: An island is a landmass that is completely surrounded by water. It can be formed through various processes, including volcanic activity, tectonic shifts, or the rising sea level.
(iv) Mangroves: Mangroves are salt-tolerant trees that grow along coastal areas, particularly in tropical and subtropical regions. They play a vital role in preventing coastal erosion and providing habitat for various species.
(v) Beach Erosion: Beach erosion is the process of the gradual removal of sand and sediment from a beach due to natural forces such as waves, currents, and storms.
(i) How are islands formed?
Ans: Islands can be formed through various processes, including volcanic activity, where underwater volcanoes build up land over time. Islands can also be formed due to tectonic shifts, where landmasses are separated by geological movements. Rising sea levels can also cause certain areas to become isolated, forming islands.
(ii) Explain how tides occur.
Ans: Tides occur due to the gravitational pull of the moon and the sun on Earth's oceans. As the moon's gravitational force affects different parts of the Earth, it creates a bulge of water, resulting in high tide. The areas opposite these bulges experience low tide. When the Earth rotates, different coastlines experience high and low tides at different times.
(iii) What is the importance of mangrove trees in coastal areas?
Ans: Mangrove trees are essential in coastal areas because their extensive root systems help stabilize the soil, preventing erosion caused by waves and currents. They also act as a buffer during storms, absorbing the impact of strong winds and waves. Mangroves provide habitats for various marine species and contribute to the overall health of coastal ecosystems.
(iv) Describe two human activities that can contribute to coastal erosion.
Ans:
(v) Why is the coastline considered a dynamic and changing environment?
Ans: The coastline is dynamic because it is shaped by various natural processes such as erosion, sediment deposition, wave action, and tides. These processes are ongoing and can cause the coastline to change its shape, size, and features over time. Human activities and environmental factors also contribute to these changes, making the coastline a continuously evolving environment.
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