OAA Science 2 — Questions and Answers
Question 1: Which organelle is responsible for producing energy (ATP) in a cell?
- Nucleus
- Mitochondria (Correct answer)
- Ribosome
- Vacuole
Correct answer: Mitochondria
Mitochondria carry out cellular respiration to produce ATP, the cell's energy currency.
Question 2: A student notices that plants near a window grow toward the light. This response is called:
- Gravitropism
- Hydrotropism
- Phototropism (Correct answer)
- Thigmotropism
Correct answer: Phototropism
Phototropism is the growth of a plant toward (or away from) a light source.
Question 3: Which type of rock is formed from cooling magma or lava?
- Sedimentary
- Metamorphic
- Igneous (Correct answer)
- Limestone
Correct answer: Igneous
Igneous rocks form when molten rock (magma or lava) cools and solidifies.
Question 4: What happens to the kinetic energy of gas particles when the temperature of the gas increases?
- It decreases
- It stays the same
- It increases (Correct answer)
- It is converted to potential energy
Correct answer: It increases
Temperature is a measure of the average kinetic energy of particles, so higher temperature means higher kinetic energy.
Question 5: Which of the following best describes a physical change?
- Wood burning in a fireplace
- Iron rusting on a fence
- Water freezing into ice (Correct answer)
- Baking soda reacting with vinegar
Correct answer: Water freezing into ice
Freezing water changes its state but not its chemical composition, making it a physical change.
Question 6: The Sun's energy reaches Earth primarily through which process?
- Conduction
- Convection
- Radiation (Correct answer)
- Evaporation
Correct answer: Radiation
Solar energy travels through the vacuum of space as electromagnetic radiation (radiant energy).
Question 7: Which layer of Earth is made of solid iron and nickel?
- Crust
- Mantle
- Outer core
- Inner core (Correct answer)
Correct answer: Inner core
The inner core is a solid ball of iron and nickel due to the enormous pressure from the layers above it.
OAA Science 2
Which organelle is responsible for producing energy (ATP) in a cell?