ISASP Science 5 — Questions and Answers
Question 1: A food web shows grass → grasshopper → frog → snake → hawk. If a disease kills most of the frogs, which population would most likely increase first?
- Snakes
- Hawks
- Grasshoppers (Correct answer)
- Grass
Correct answer: Grasshoppers
With fewer frogs eating grasshoppers, the grasshopper population would likely increase due to reduced predation.
Question 2: Which of the following best explains why planets orbit the Sun rather than moving in straight lines through space?
- The Sun emits radiation that pushes planets into circular paths
- The Sun's gravity continuously curves the path of each planet (Correct answer)
- Planets were created already moving in orbits
- Magnetic forces from the Sun hold planets in orbit
Correct answer: The Sun's gravity continuously curves the path of each planet
The Sun's gravity acts as a centripetal force that continuously bends each planet's path into an elliptical orbit.
Question 3: Which process causes rocks to break down into smaller pieces through physical means without changing their chemical composition?
- Chemical weathering
- Erosion
- Mechanical weathering (Correct answer)
- Deposition
Correct answer: Mechanical weathering
Mechanical (physical) weathering breaks rocks into smaller pieces through forces like ice expansion, abrasion, and plant roots — no new minerals form.
Question 4: An atom of carbon has 6 protons, 6 neutrons, and 6 electrons. What is the overall charge of this atom?
- +6
- -6
- 0 (neutral) (Correct answer)
- +12
Correct answer: 0 (neutral)
An atom is electrically neutral when the number of protons (positive) equals the number of electrons (negative), so 6 protons and 6 electrons cancel out.
Question 5: Which of the following correctly describes the relationship between wavelength and frequency of electromagnetic waves?
- Longer wavelength means higher frequency
- Shorter wavelength means higher frequency (Correct answer)
- Wavelength and frequency are not related
- Frequency decreases as the wave's speed increases
Correct answer: Shorter wavelength means higher frequency
Since all electromagnetic waves travel at the same speed (speed of light), shorter wavelengths must complete more cycles per second, meaning higher frequency.
Question 6: Which type of genetic mutation involves a single base in the DNA sequence being substituted for a different base?
- Deletion mutation
- Insertion mutation
- Point (substitution) mutation (Correct answer)
- Frameshift mutation
Correct answer: Point (substitution) mutation
A point mutation (or substitution) is when one nucleotide base is replaced by a different base in the DNA sequence.
Question 7: Iowa experiences four distinct seasons because:
- Earth's distance from the Sun changes significantly throughout the year
- Earth's axis is tilted at about 23.5°, changing the angle of sunlight reaching Iowa (Correct answer)
- The Sun produces more energy in summer than in winter
- Iowa is located far from the equator where temperature extremes are greater
Correct answer: Earth's axis is tilted at about 23.5°, changing the angle of sunlight reaching Iowa
Earth's 23.5° axial tilt causes different parts of Earth to receive more direct sunlight at different times of year, creating the seasons.
ISASP Science 5
A food web shows grass → grasshopper → frog → snake → hawk.
If a disease kills most of the frogs, which population would most likely increase first?