Unit 4 Pretest: The Universe

Front

What type of galaxy has no symmetrical shape?

Back

Irregular galaxy.

Front

What is a large celestial body that is composed of gas and emits light?

Back

Star.

Front

Why is studying red shift important to astronomers?

Back

It provides evidence that the universe is expanding.

Front

What is the primary factor that determines the lifecycle path of stars?

Back

Mass.

Front

Which type of galaxy contains a central bulge of old stars?

Back

Spiral galaxy.

Front

What are the three main types of galaxies?

Back

Spiral, elliptical, and irregular.

Front

What is the difference between a star and a planet?

Back

A star emits light and heat through nuclear fusion, while a planet does not emit light and orbits a star.

Front

What is the significance of the Big Bang theory?

Back

It explains the origin of the universe and its expansion.

Front

What is a nebula?

Back

A large cloud of gas and dust in space, often the birthplace of stars.

Front

What is the role of gravity in the formation of stars?

Back

Gravity pulls together gas and dust to form stars.