Chapter 2, Sections 1 and 2 Homework

Chapter 2 Section 1

1. Describe the different surfaces and geographical areas found on Earth.

Answer:
The main different surfaces of earth are land, water, and air.  Land is made of continents, islands, and the land beneath the oceans called ocean basins.  Water makes up 70 percent of the planet's surface and consists of oceans, lakes, rivers, and any other bodies of water.  Air is the last surface.  It's called the atmosphere and extends from the planet's surface.  Air is made up of 78 percent nitrogen, 21 percent oxygen, and one percent other gases.

2. What point on Earth is the greatest distance from sea level?

Answer:

The greatest distance above sea level is Mount Everest.

Creative Writing: Agree or disagree with the statement: When small objects in space, such as meteoroids and comets, enter Earth’s atmosphere, they have no long-term effect on Earth’s lithosphere, atmosphere, or biosphere. Justify your conclusion.

Answer: 

I think that meteoroid and comet landings do have long term affects in the lithosphere, atmosphere, and the biosphere.  If the meteoroid or comet is big enough, they'll leave a dent in the lithosphere forever.  Trees and animals may live in that crater, but the crater will always be there.  I think that comets and meteoroids may affect the atmosphere too.  When the go through the atmosphere the catch fire because of friction with our atmosphere.  If the falling object suffers from the friction, why shouldn't our atmosphere?  The landings of the comets and meteoroids can also affect the biosphere for the worse.  If it were big enough, it could annihilate a whole species in a certain area, or damage the environment they live in.

Chapter 2, Section 2

1. How do Earth’s layers contribute to the planet’s physical characteristics?

Answer:

The mantle, or the second layer of the earth, affect the planet's characteristics a whole lot.  The mantle oozes out currents of very hot rock below the crush, causing the plates to move around slowly.  Sometimes whole continents collide with one another, creating huge mountains and valleys.  The mantle also bursts magma through the cracks at the bottom of the ocean, gradually forming underwater mountains that emerge as islands.  One these islands, and even on continents, magma will continue to flow periodically, causing a volcanic eruption and shaping the surface even more by adding more rock and fertile soil for new plants.

2. How do internal forces of change affect Earth’s surface differently from external forces of change?

Answer:
Internal forces of change usually just change the earth and create mountains, volcanoes, and new features.  The external forces weather away at the surface, destroying rather than creating.

Creative Writing: Describe how internal forces may have changed the surface of what is now North America over the past 225 million years.

Answer:

Over time the mantle's flow has moved the plates under North America around, shifting and shaping it into the way it is formed today.  Multiple collisions with other continents and islands have bunched up the land, forming it into mountains and valleys.  Earthquakes throughout the continent have pushed land masses around and snap pieces of land apart.  Volcanic eruptions have dotted the surface of North America, providing more soil and rebirth of plants and nature.