Review Questions for Science Assessment

What is the main function of the mitochondria in a cell?

• To store genetic information

• To produce energy

• To control cell division

• To provide structural support

Answer explanation

The main function of mitochondria is to produce energy in the form of ATP through cellular respiration, making them the powerhouse of the cell. This distinguishes them from other organelles that have different roles.

Which of the following is an example of a physical change?

• Rust forming on iron

• Ice melting into water

• Wood burning in a fire

• Milk souring

Answer explanation

Ice melting into water is a physical change because it alters the state of water without changing its chemical composition. In contrast, rust formation, burning wood, and souring milk involve chemical changes.

Which of these planets is known for having the largest storm in the solar system, the Great Red Spot?

• Mars

• Jupiter

• Saturn

• Neptune

Answer explanation

Jupiter is known for the Great Red Spot, a massive storm that has been raging for centuries. This storm is the largest in the solar system, making Jupiter the correct answer.

Which of the following best describes the role of producers in an ecosystem?

• They break down dead organisms.

• They create energy from the sun through photosynthesis.

• They consume other organisms for food.

• They provide shelter for animals.

Answer explanation

Producers, such as plants, create energy through photosynthesis by converting sunlight into chemical energy. This process is fundamental to ecosystems, as it forms the base of the food chain, unlike the other options listed.

What type of energy is stored in food?

• Kinetic energy

• Chemical energy

• Thermal energy

• Nuclear energy

Answer explanation

Food contains chemical energy, which is stored in the bonds of its molecules. When we consume food, our bodies convert this chemical energy into usable energy for various functions.

The water cycle is driven primarily by which form of energy?

• Nuclear energy

• Solar energy

• Kinetic energy

• Gravitational energy

Answer explanation

The water cycle is primarily driven by solar energy, which heats water in oceans and lakes, causing evaporation. This energy is essential for the processes of condensation and precipitation that make up the cycle.

How does the process of photosynthesis benefit animals?

• It creates oxygen for animals to breathe.

• It provides energy for animal movement.

• It breaks down food for animals to consume.

• It provides heat for animals.

Answer explanation

Photosynthesis benefits animals by producing oxygen, which is essential for their respiration. Without this process, animals would not have the oxygen needed to breathe and survive.

What is the primary cause of seasons on Earth?

• The Earth's distance from the Sun

• The tilt of the Earth's axis

• The speed of the Earth's rotation

• The Moon's gravitational pull

Answer explanation

The primary cause of seasons on Earth is the tilt of the Earth's axis. This tilt causes different parts of the Earth to receive varying amounts of sunlight throughout the year, leading to the changing seasons.

Which of these statements about the electromagnetic spectrum is true?

• All electromagnetic waves travel at different speeds.

• X-rays have a longer wavelength than visible light.

• Microwaves have a shorter wavelength than ultraviolet rays.

• Radio waves have the longest wavelength.

Answer explanation

Radio waves indeed have the longest wavelength in the electromagnetic spectrum, while X-rays have shorter wavelengths than visible light, and microwaves have longer wavelengths than ultraviolet rays.

Which process is responsible for the formation of clouds?

• Precipitation

• Condensation

• Evaporation

• Runoff

Answer explanation

Clouds form through the process of condensation, where water vapor in the air cools and changes into liquid droplets, creating clouds. Evaporation is the process that leads to vapor, but condensation is what forms clouds.