Earth & Space science
What is the star at the center of our solar system?
The Sun
What happens to most solids when they are heated?
They expand because their particles move faster and spread out.
What do plants need to make their own food?
Sunlight, water, and carbon dioxide.
What is the first step of the scientific method?
Asking a question.
What organ pumps blood through your entire body?
The Heart
What causes day and night on Earth?
Earth’s rotation on its axis.
What kind of energy does a flashlight use to produce light?
Electrical energy, which is changed into light energy.
What is a habitat?
A place where an organism lives and gets what it needs to survive.
What tool do scientists use to measure temperature?
A thermometer.
What organ controls your thoughts, movements, and senses?
The Brain
Why is the Sun important for life on Earth?
The Sun provides light and heat energy, which plants need to make food and which keeps Earth warm enough for living things.
Why does a ball roll farther on a smooth floor than on a carpet?
Because the smooth floor has less friction, so it doesn’t slow the ball down as much.
Why do animals need to eat plants or other animals to survive?
Because animals cannot make their own food, so they must get energy and nutrients by eating plants or other animals.
Why is it important to write down observations during an experiment?
Because observations help scientists remember what happened and compare results later.
Why are your lungs important for your body?
The acid breaks food down into smaller pieces so your body can absorb the nutrients.
Why do we only see one side of the Moon from Earth, even though the Moon is rotating?
Because the Moon rotates on its axis at the same rate that it orbits Earth.
Why does a metal spoon feel colder than a wooden spoon, even if they’re both in the same room?
Because metal is a better conductor of heat, so it pulls heat away from your hand faster than wood.
Why do plants in the desert have small or waxy leaves?
To reduce water loss. Small or waxy leaves help plants keep moisture in a hot, dry environment.
Why do scientists use graphs instead of just writing down numbers?
Because graphs make patterns and changes easier to see, helping scientists understand results more clearly.
Why does the heart need to pump blood nonstop?
Because blood carries oxygen and nutrients to every organ, and without a constant supply, the organs can’t work properly.
Why does the Moon look brighter during a full moon?
Because the entire sunlit side of the Moon is facing Earth, so it reflects more sunlight toward us.
Why does black absorb more heat than white?
Because black absorbs most of the light that hits it, while white reflects most of the light.
Why do predators and prey often evolve to become faster over time?
Because predators that are faster catch more food, and prey that are faster escape more often.
Why is it important for scientists to control variables in an experiment?
Because controlling variables makes sure that only one factor is being tested, so scientists can know exactly what caused the results.
Why is the brain considered the control center of the body?
Because it sends and receives signals through the nerves, telling every organ and muscle what to do.