8th Science STAAR Review

Front

What type of interaction exists between shrimp and blue crabs in a food web?

Back

Shrimp compete with blue crabs for food.

Front

What is a fundamental concept of the cell theory?

Back

Living organisms are composed of one or more cells.

Front

What is the formula to calculate average speed?

Back

Average speed = Total distance / Total time.

Front

If a car travels at a constant speed of 15 m/s for 2 minutes, how far does it travel?

Back

Distance = Speed x Time = 15 m/s x 120 s = 1800 m.

Front

What does each grain of sand represent in a model of a galaxy?

Back

Each grain of sand represents a star.

Front

What is the average speed of a student who rode a bicycle 15 miles in 90 minutes?

Back

10 mph.

Front

What is competition in an ecosystem?

Back

Competition occurs when two or more organisms vie for the same resources, such as food or space.

Front

What is the role of decomposers in an ecosystem?

Back

Decomposers break down dead organic matter, returning nutrients to the soil.

Front

What is the difference between speed and velocity?

Back

Speed is a scalar quantity (magnitude only), while velocity is a vector quantity (magnitude and direction).

Front

What is the significance of the cell membrane?

Back

The cell membrane controls what enters and exits the cell, maintaining homeostasis.