Exploring Science: Concepts and Energy

Nora is helping her friend Anika take care of a garden. They notice that all the plants look a little different, even though they are the same type. Nora wonders what inside the plants makes them unique. What is DNA mainly responsible for in living things?

• Giving energy to cells

• Carrying genetic information

• Making food

Answer explanation

DNA is mainly responsible for carrying genetic information in living things. It contains the instructions needed for growth, development, and reproduction, which is essential for both plants and animals.

Olivia is walking in a park and sees a rock, a tree, some water, and feels the air. Which of the following is a living thing?

• Rock

• Tree

• Air

Answer explanation

A tree is a living organism that grows, reproduces, and responds to its environment, unlike a rock, water, or air, which are non-living things. Therefore, the correct answer is a tree.

Benjamin is reading a book at night and wants to see clearly. Which of these should he use as a source of light?

• The Moon

• The Sun

• A Book

Answer explanation

The Sun is a natural source of light, emitting its own light through nuclear fusion. The Moon reflects sunlight but does not produce light itself, while a mirror and a book do not generate light either.

Michael is looking for ways to power his home using environmentally friendly sources. Which of these is a renewable source of energy?

• Coal

• Wind

• Natural gas

Answer explanation

Wind is a renewable source of energy because it is generated from natural processes that are continuously replenished. In contrast, coal, oil, and natural gas are fossil fuels that deplete over time.

Daniel wants to build a simple circuit to light up a bulb. Which of the following should he use to CONDUCT electricity in his circuit?

• Plastic

• Wood

• Metal wire

Answer explanation

Metal wire is used to conduct electricity in a simple circuit because it is a good conductor, allowing electric current to flow easily. In contrast, materials like plastic, wood, and paper are insulators and do not conduct electricity.

Luna wants to read her book at night, so she turns on a device that changes electrical energy into LIGHT ENERGY. Which device does Luna use?

• Battery

• Light bulb

• Wire

Answer explanation

A light bulb converts electrical energy into light energy through the process of incandescence or fluorescence, making it the correct choice. A battery stores energy, a switch controls flow, and a wire conducts electricity.

David is curious about what causes the wind to blow on Earth. He wonders what the main source of wind energy is. What should David learn is the main source?

• The Moon

• The Sun

• Oceans

Answer explanation

The main source of wind energy on Earth is the Sun. It heats the Earth's surface unevenly, creating temperature differences that lead to air movement, which we experience as wind.

Charlotte is curious about how traits are passed from parents to their children. Which of these best describes how DNA is passed from parents to offspring?

• Through air

• Through seeds or eggs

• By eating food

Answer explanation

DNA is passed from parents to offspring primarily through reproductive cells, which are found in seeds and eggs. This process ensures genetic information is transmitted to the next generation.

Michael is using a flashlight in a dark room. He places a MIRROR in front of the flashlight. What happens to the light?

• The light disappears

• The light is absorbed

• The light is reflected

Answer explanation

When a mirror is placed in front of a flashlight, the light bounces off the mirror's surface. This process is known as reflection, which is why the correct answer is that the light is reflected.

Mia is watching a thunderstorm from her window. She notices that she always sees the lightning before she hears the thunder. Why does this happen?

• Sound travels faster than light

• Light travels faster than sound

• They travel at the same speed

Answer explanation

We hear thunder after seeing lightning because light travels faster than sound. This means we see the flash of lightning before the sound of thunder reaches us.