GED Science Test #7 3 — Questions and Answers
Question 1: A scientist observes that a population of bacteria doubles every 20 minutes under ideal conditions. What type of growth pattern does this represent?
- Linear growth
- Exponential growth (Correct answer)
- Logistic growth
- Arithmetic growth
Correct answer: Exponential growth
Exponential growth occurs when a population multiplies by a constant factor over equal time intervals, such as doubling every 20 minutes.
Question 2: Which of the following best explains why ice floats on liquid water?
- Ice is colder than liquid water
- Ice molecules move faster than liquid water molecules
- Ice is less dense than liquid water due to hydrogen bonding (Correct answer)
- Ice has a higher molecular weight than liquid water
Correct answer: Ice is less dense than liquid water due to hydrogen bonding
Water molecules in ice form a crystalline lattice held together by hydrogen bonds, creating a less dense structure than liquid water.
Question 3: During photosynthesis, what happens to carbon dioxide molecules?
- They are released as a byproduct
- They are broken down to release energy
- They are converted into glucose using light energy (Correct answer)
- They are combined with oxygen to form water
Correct answer: They are converted into glucose using light energy
In photosynthesis, plants use light energy to convert carbon dioxide and water into glucose and oxygen.
Question 4: A car traveling at 60 mph applies its brakes and stops after 4 seconds. What physical concept explains the car's resistance to stopping?
- Gravity
- Inertia (Correct answer)
- Friction
- Momentum transfer
Correct answer: Inertia
Inertia is the tendency of an object in motion to remain in motion, which causes the car to resist the change in its state of motion.
Question 5: Which layer of the Earth is responsible for generating Earth's magnetic field?
- The crust
- The mantle
- The outer core (Correct answer)
- The inner core
Correct answer: The outer core
Earth's magnetic field is generated by the movement of molten iron and nickel in the liquid outer core.
Question 6: A student notices that plants in a shaded area have larger, thinner leaves than plants of the same species in full sunlight. This is an example of:
- Genetic mutation
- Phenotypic plasticity (Correct answer)
- Natural selection
- Genetic drift
Correct answer: Phenotypic plasticity
Phenotypic plasticity is the ability of an organism to change its physical characteristics in response to environmental conditions without changing its genes.
Question 7: What is the main difference between a physical change and a chemical change?
- Physical changes involve heat; chemical changes do not
- Chemical changes produce new substances; physical changes do not (Correct answer)
- Physical changes are permanent; chemical changes are reversible
- Chemical changes occur faster than physical changes
Correct answer: Chemical changes produce new substances; physical changes do not
A chemical change results in the formation of one or more new substances with different properties, while a physical change alters only the form or appearance of a substance.
GED Science Test #7 3
A scientist observes that a population of bacteria doubles every 20 minutes under ideal conditions.
What type of growth pattern does this represent?