what must a sound wave travel through in order to be heard?
a medium
What causes surface currents to move in a circular pattern?
the earth's rotation
Mountains, Valleys, plains
what is an ecosystem?
all the living and nonliving things in one area
what is soil made of?
loose material, weathered rock, water, air, and humus
what pattern does a longitudinal wave have?
back and forth
What determines the size of a wave?
the strength of the wind, how long the wind blows, and the distance the wind blows
which part of the ocean floor is the steep boundary between the continental shelf and the deeper ocean floor?
the continental slope
which zone of the ocean does not receive any sunlight?
the dark zone
what is humus?
part of the soil that contains decayed plant and animal material
what term describes the quality of a sound?
timbre
why does freshwater flow downhill?
gravity
what is the flat, deep floor of the ocean called?
ocean plain
which zone of the ocean receives the most sunlight?
the sunlight zone
what soil type has the largest particle size?
sand
How many symbols does binary code use?
two
What are deep ocean currents affected by?
the salt in the water and the temperature of the water
why is it hard for scientists to explore the ocean plains?
because the plains are so deep
how are photoplankton able to receive sunlight in the ocean?
they live close to the oceans surface
what is the difference between the weathering and erosion?
weathering breaks down rock, erosion moves it from one place to another.
Who invented the telephone?
Alexander Graham Bell
The largest and deepest ocean is the _________
Pacific Ocean
what are three features in the ocean that are not found on land?
continental shelf, continental slope, deep trenches
What is a food web?
several food chains linked together
what is the area of sediment at the mouth of a river called?
a delta