8th Grade Science STAAR Review

Front

Which of the following best describes a relationship in this grassland? Upland sandpipers are primary and secondary consumers because they eat grasses and grasshoppers.

Back

Upland sandpipers are primary and secondary consumers.

Front

Which statement about stars is correct? Options: Star formation begins in a nebula., White dwarfs become main-sequence stars when they gain mass., Supergiants are stars that can absorb black holes., Main-sequence stars are formed by comets.

Back

Star formation begins in a nebula.

Front

Based on their observations, can the students correctly conclude that a chemical reaction occurred?

Back

Yes, because a new material of a different color formed on part of the metal strip.

Front

Which statement describes the energy changes that occur when water in a tea kettle is heated on a stove that uses natural gas?

Back

Some of the chemical energy in the natural gas transforms into thermal energy, which heats the water. Then some of the thermal energy changes into sound energy when the water forms steam and the steam leaves the kettle.

Front

What most likely happened after a patient was given an antibiotic for a bacterial infection and got sick again with the same type of infection after 10 days? Options: A few bacteria survived the antibiotics and stopped reproducing. The patient’s high fever inactivated the antibiotic, allowing the surviving bacteria to grow rapidly. The antibiotic slowed the life cycle of the bacteria. Some of the bacteria were resistant to the antibiotic, and they reproduced.

Back

Some of the bacteria were resistant to the antibiotic, and they reproduced.

Front

A 1,100 kg car comes uniformly to a stop. If the vehicle is accelerating at - 1.2 m/s², which force is closest to the net force acting on the vehicle?

Back

-1,300 N

Front

Why does autumn start in different months of the year in North America and South America?

Back

Earth’s axis has a 23.5° tilt.

Front

What is the primary function of this body system?

Back

The transport of nutrients, water, and oxygen to body cells

Front

Increased biodiversity results in a more sustainable ecosystem because —

Back

a greater variety of species present allows more organisms to adapt after changes occur

Front

How many valence electrons are in an atom of each element in Group 15 in the periodic table?

Back

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