The convection currents are what causes the movement of the tectonic plates. These currents occur in the mantle layer. Basically, the convection currents are a circular movement of the magma in the mantle which is cause by the difference in temperature and density. The hotter magma moves up because it is less dense, while the cooler magma moves down because it is more dense. This movement continues all the time. The magma that moves up comes in touch with the crust above it. At certain places where the crust is thinner, or there are cracks, under the big pressure from the mantle, the magma manages to penetrate through it, filling up the gaps, and also pushing the plates away. As the plates are pushed more and more, their opposite ends collide with other plates, resulting in subduction, so the crust is getting into the mantle and melts, moving down in the mantle as it is becoming cooler and denser magma, and the process continues on and on.
Answer:
"water, air, sunlight, soil, plants, microorganisms, insects and animals. Ecosystems may be terrestrial – that is, on land – or aquatic. Sizes of ecosystems vary; they could entail a small puddle or an enormous swath of desert. Likewise, natural ecosystems can look quite different from one another."
Explanation:
Answer:
Peru
Explanation:
Machu picchu is located in the Andes mountains in Peru
Answer:
A globe is a three dimensional representation of the Earth. It is a simpler model of the Earth.
Two advantages of a globe are:
It shows us the correct shapes and sizes of the land and water masses.
It gives us a good visual indication of the Earth’s surface.
Two limitations of using a globe are:
It is not easy to carry a globe from one place to the other due to its big size.
A globe does not show us various features like the vegetation and the climate of a place.
Explanation:
Answer: Africa includes the rich source of water drainage in the form of rivers.
Explanation:
The course travelled by the major rivers in Africa are as follows:
1. Congo: Center to north and further to the Western region finally drains into the Atlantic Ocean.
2. Nile: Northeastern part to the North and then finally to the Mediterranean Sea.
3. Zambezi: South eastern to Indian Ocean.
4. Niger: West to the Guinea Gulf.