Chapter 5 Oceans 4th Grade

Front

What is salinity?

Back

Salinity is the measure of the amount of salt dissolved in water, usually expressed in parts per thousand (ppt).

Front

At what depth is the salinity level typically the lowest in the ocean?

Back

The salinity level is typically the lowest at 1000 meters depth.

Front

What is phytoplankton?

Back

Phytoplankton are tiny, photosynthetic organisms that live in the ocean and are a crucial part of the marine food web.

Front

What is a hypothesis?

Back

A hypothesis is a proposed explanation or prediction that can be tested through investigation.

Front

What type of organism is a sea urchin?

Back

A sea urchin is a non-moving organism that adheres to ocean floor surfaces and is part of the marine food web.

Front

What is the main cause of ocean tides?

Back

The main cause of ocean tides is the Moon’s gravitational pull.

Front

What is the role of zooplankton in the ocean?

Back

Zooplankton are small, drifting animals that feed on phytoplankton and are an important part of the marine food web.

Front

What is the ocean floor called?

Back

The ocean floor is called the seabed or benthic zone.

Front

What are ocean trenches?

Back

Ocean trenches are deep, narrow depressions in the ocean floor, often the deepest parts of the ocean.

Front

What is the photic zone?

Back

The photic zone is the upper layer of the ocean where sunlight penetrates, allowing photosynthesis to occur.