Free NeSA Science Questions and Answers — Questions and Answers
Question 1: Which process is primarily responsible for the oxygen in Earth’s atmosphere?
- Respiration
- Photosynthesis (Correct answer)
- Combustion
- Fermentation
Correct answer: Photosynthesis
Photosynthesis is the biological process by which green plants, algae, and some bacteria convert light energy into chemical energy, producing glucose and releasing oxygen as a byproduct. This process is responsible for generating nearly all the oxygen present in Earth's atmosphere.
Question 2: What is the main function of the roots in a plant?
- To produce seeds
- To carry out photosynthesis
- To absorb water and nutrients (Correct answer)
- To protect the plant from herbivores
Correct answer: To absorb water and nutrients
The primary function of a plant's roots is to anchor the plant firmly in the soil and, most importantly, to absorb water and essential mineral nutrients from the soil. These absorbed substances are then transported to other parts of the plant to support growth and other metabolic processes.
Question 3: Which layer of Earth is composed mostly of liquid iron and nickel?
- Crust
- Mantle
- Outer core (Correct answer)
- Inner core
Correct answer: Outer core
The Earth's outer core is a liquid layer composed primarily of molten iron and nickel. This layer is responsible for generating Earth's magnetic field through the convection currents of its metallic fluid, distinguishing it from the solid inner core and the rocky mantle and crust.
Question 4: What type of energy transformation occurs in a solar panel?
- Chemical to electrical
- Mechanical to electrical
- Thermal to electrical
- Light to electrical (Correct answer)
Correct answer: Light to electrical
Solar panels, specifically photovoltaic cells, are designed to convert light energy (from the sun) directly into electrical energy. This process involves photons striking the semiconductor material in the panel, exciting electrons and creating an electric current, without an intermediate thermal or mechanical step.
Question 5: Which of the following best describes the function of the mitochondria in a cell?
- They store genetic information.
- They produce proteins.
- They generate energy. (Correct answer)
- They digest waste materials.
Correct answer: They generate energy.
Mitochondria are often referred to as the 'powerhouses' of the cell because their primary function is to generate the majority of the cell's supply of adenosine triphosphate (ATP). ATP is the main energy currency of the cell, produced through cellular respiration to fuel various cellular activities.
Free NeSA Science Questions and Answers
Which process is primarily responsible for the oxygen in Earth’s atmosphere?