HiSET Science Practice Test #3 3 — Questions and Answers
Question 1: Which of the following best describes natural selection?
- Organisms deliberately adapt to their environment over their lifetime
- Individuals with favorable traits are more likely to survive and reproduce, passing traits to offspring (Correct answer)
- All members of a species change simultaneously in response to environmental pressure
- Random mutations always lead to improvements in a species
Correct answer: Individuals with favorable traits are more likely to survive and reproduce, passing traits to offspring
Natural selection is the process by which individuals with traits better suited to their environment tend to survive longer and reproduce more, causing those traits to become more common over generations.
Question 2: Which blood vessel carries oxygenated blood away from the heart to the body?
- Vena cava
- Pulmonary vein
- Aorta (Correct answer)
- Pulmonary artery
Correct answer: Aorta
The aorta is the largest artery in the body. It carries oxygenated blood from the left ventricle of the heart and distributes it to the rest of the body through branching arteries.
Question 3: What is the half-life of a radioactive substance?
- The time it takes for the substance to completely decay
- The time for half the atoms in a radioactive sample to decay (Correct answer)
- The point at which radiation becomes harmless
- The average age of radioactive materials
Correct answer: The time for half the atoms in a radioactive sample to decay
Half-life is the time required for half of the radioactive atoms in a sample to decay into other elements or isotopes. After two half-lives, one quarter of the original material remains, and so on.
Question 4: Which of the following is a renewable energy source?
- Coal
- Natural gas
- Nuclear fission
- Solar power (Correct answer)
Correct answer: Solar power
Solar power is renewable because it comes from the sun, which will continue producing energy for billions of years. Coal and natural gas are fossil fuels (non-renewable). Nuclear fission uses uranium, which is a finite resource.
Question 5: What is the main function of red blood cells?
- Fight infection and disease
- Help blood clot after injury
- Transport oxygen throughout the body (Correct answer)
- Produce antibodies
Correct answer: Transport oxygen throughout the body
Red blood cells (erythrocytes) contain hemoglobin, a protein that binds to oxygen in the lungs and transports it to tissues throughout the body. White blood cells fight infection; platelets help with clotting.
Question 6: When two tectonic plates collide and one is forced beneath the other, this is called:
- Transform boundary
- Divergent boundary
- Subduction (Correct answer)
- Seafloor spreading
Correct answer: Subduction
Subduction occurs at convergent plate boundaries when a denser plate (usually oceanic) is forced beneath a less dense plate (usually continental) as they collide. The subducted plate melts in the mantle.
HiSET Science Practice Test #3 3
Which of the following best describes natural selection?