GED Science Test #9 3 ā Questions and Answers
Question 1: Which statement best describes the difference between a food chain and a food web?
- A food chain shows one path of energy flow, while a food web shows multiple interconnected paths (Correct answer)
- A food web only includes animals, while a food chain includes all organisms
- A food chain shows all relationships in an ecosystem, while a food web shows one
- There is no difference ā they are the same concept
Correct answer: A food chain shows one path of energy flow, while a food web shows multiple interconnected paths
A food chain shows a linear sequence of who eats whom. A food web is more realistic ā it shows the complex, interconnected feeding relationships among many organisms in an ecosystem.
Question 2: The element with atomic number 6 is carbon. How many electrons does a neutral carbon atom have?
- 6 (Correct answer)
- 12
- 3
- 8
Correct answer: 6
A neutral atom has the same number of electrons as protons. Since carbon has an atomic number of 6 (6 protons), it also has 6 electrons in its neutral state.
Question 3: Scientists have found similar fossilized organisms on continents that are now separated by oceans. This evidence supports the theory of:
- Continental drift (plate tectonics) (Correct answer)
- Natural selection
- The Big Bang
- Spontaneous generation
Correct answer: Continental drift (plate tectonics)
Matching fossils on separated continents provide evidence that those landmasses were once connected. This supports the theory of continental drift, showing that today's continents were once part of a single supercontinent (Pangaea).
Question 4: Which type of electromagnetic radiation has the highest frequency?
- Gamma rays (Correct answer)
- X-rays
- Ultraviolet light
- Microwaves
Correct answer: Gamma rays
The electromagnetic spectrum, ordered from lowest to highest frequency: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays. Gamma rays have the highest frequency and most energy.
Question 5: When a ball is thrown upward, at the highest point, the ball's:
- Velocity is zero but acceleration due to gravity continues downward (Correct answer)
- Velocity and acceleration are both zero
- Velocity is maximum and acceleration is zero
- Both velocity and acceleration are directed upward
Correct answer: Velocity is zero but acceleration due to gravity continues downward
At the highest point, the ball momentarily stops (velocity = 0), but gravity (9.8 m/s² downward) still acts on it. This is why the ball then falls back down ā gravity never stops pulling.
Question 6: The nervous system transmits signals using specialized cells called:
- Neurons (Correct answer)
- Nephrons
- Nuclei
- Nodules
Correct answer: Neurons
Neurons are the basic functional units of the nervous system. They transmit electrical and chemical signals throughout the body. Neurons consist of a cell body, dendrites (receive signals), and an axon (sends signals).
Which statement best describes the difference between a food chain and a food web?