The globe

   1. The globe

   The Earth has been changing over time, but that change is so slow that several generations of men are needed to make this visible. The life of people is counted in years, while the life of the Earth is counted in thousands of centuries.

   In the Earth's history, we can distinguish several major eras or periods, each one of them comprises millions of years. These are the eras :

   - Archaic: the most primitive era.

   - Paleozoic: where life appears with very simple species.

   - Mesozoic: it is characterized by the appearance of reptiles.

   - Cenozoic: mammals appear.

   - Quaternary: the man appears on Earth.


  2. Choose one of these words and answer: Archaic, Paleozoic, Mesozoic, Cenozoic, Quaternary
 

Simple species appear

It is the most primitive

Reptiles appear

Life appears

Mammals appear

Man appears


   3. Structure of the Earth

   The globe is formed by the following spheres:
   - The endosphere is the inner Earth's core that is composed of heavy materials.
   - The lithosphere is the crust with a thickness that ranges between 60 and 120 kilometers.
   - The hydrosphere is formed by the waters of the oceans and seas with an average depth of 4,700 meters.
   - The atmosphere is the gaseous layer that surrounds the Earth. Its thickness is about 700 kilometers.


    4. Choose one of the following Earth's spheres: endosphere, lithosphere, hydrosphere and atmosphere:

It is the gaseous layer

It forms the inner core

They are the seas and oceans

Its thickness is about 700 km.

It forms the crust

It is composed of heavy materials

The depth is 4,700 m

Its thickness ranges between 60 and 120 km.






    5. Contrasts of the globe
   On the Earth's surface, we see sunken zones occupied by oceans and seas and projections or elevated zones which form the continents and islands. But the distribution of lands and seas is very unequal in two ways:
- The seas have an area three times larger than the land. While the land is covered by the 72% of water, the land only covers 28%.

- There is more land in the Northern Hemisphere than in the Southern Hemisphere. The continents in the Northern Hemisphere occupy 39% and in the Southern Hemisphere 17%.

   In the side picture, we see the greatest surface of the water and the greatest proportion of land (black color) in the Northern Hemisphere.


   6. Answer if these sentences are true or false:

The sunken zones are continents

There is more surface of oceans and seas

The land occupies 28%

The oceans occupies 39%

In the Northern Hemisphere, the land covers 17%

The waters occupy 72%

In the south, the land covers 17%


    7. Continents, peninsulas and islands

   The continents occupy 149 000 000 square kilometers distributed in this way:
   - Europe: 10 000 000 km2

   - Asia: 44 150 000 km2.

   - Africa: 30 500 000 km2.
   - North America: 24,000,000 km2.
   - South America: 18 000 000 km2.
   - Oceania: 9 000 000 km2.
   - Antarctica Continent or Antarctic: 14 000 000 km2.

   The peninsulas are pieces of land that are bordered by water on all sides except one which connects to the continent called the isthmus. Spain and Portugal make up the Iberian Peninsula.
   The islands are pieces of land that are surrounded by water. The collection of islands is called archipelago.


   8. Oceans and Seas

   Waters occupy 366 000 000 km2 and they are divided in oceans and seas.
   The oceans are very large expanses of sea that cover different continents. The oceans are:
   - Pacific: 126 900 000 km2
   - Atlantic: 58 000 000 km2
   - Indian: 42 400 000 km2
   - Antarctic: 85 000 000 km2
   - Arctic: 14 100 000 km2

   Seas are smaller than oceans. They are classified into:
   - Open sea: it widely communicates with the ocean. For example: the North Sea and the Atlantic Ocean.
   - Inland Sea: it communicates with the ocean by a strait. For example: The Mediterranean Sea is connected to the Atlantic Ocean through the Strait of Gibraltar.
   - Enclosed sea: it is on one continent and does not communicate with the oceans. For example: the Caspian Sea.


   6. Indicate if these sentences are true or false:

An island has several archipelagos

The peninsula has an isthmus

Asia is larger than Africa

The largest ocean is the Atlantic

The seas are bigger than oceans

The North Sea is an open sea

The Caspian is an enclosed sea



 
If you are registered, please enter your data
 
Name:

Password:

 

Registration Information

| Educational applications | Geography
 In Spanish  | To print  | 
 Google Map |

®Arturo Ramo García.-Record of intellectual property of Teruel (Spain) No 141, of 29-IX-1999
Plaza Playa de Aro, 3, 1º DO 44002-TERUEL