FTCE Science 5 — Questions and Answers
Question 1: Which best explains why planets orbit the Sun in elliptical paths rather than circular ones?
- Planets are pushed by solar winds in one direction
- Gravitational attraction varies with distance, creating curved elliptical orbits (Correct answer)
- Planets orbit in circles but appear elliptical due to Earth's atmosphere
- The Sun's magnetic field deflects planets into elliptical paths
Correct answer: Gravitational attraction varies with distance, creating curved elliptical orbits
Kepler's First Law states that planetary orbits are ellipses with the Sun at one focus, a result of gravitational force varying with distance.
Question 2: In genetics, if two heterozygous parents (Tt × Tt) are crossed, what is the probability of offspring showing the dominant phenotype?
- 25%
- 50%
- 75% (Correct answer)
- 100%
Correct answer: 75%
A Tt × Tt cross produces a 3:1 phenotype ratio (TT, Tt, Tt, tt), meaning 75% of offspring express the dominant phenotype.
Question 3: Which energy transformation occurs when a battery-powered flashlight is turned on?
- Mechanical → electrical → light
- Chemical → electrical → light (Correct answer)
- Thermal → electrical → light
- Nuclear → electrical → light
Correct answer: Chemical → electrical → light
A battery converts stored chemical energy into electrical energy, which the bulb then converts into light (and some heat).
Question 4: A teacher is explaining natural selection. Which scenario best illustrates the concept of survival of the fittest?
- A farmer selectively breeds cows to increase milk production
- Bacteria with a mutation for antibiotic resistance survive treatment and reproduce more (Correct answer)
- A dog learns to sit through repeated reward training
- Scientists engineer a plant to resist drought conditions
Correct answer: Bacteria with a mutation for antibiotic resistance survive treatment and reproduce more
Bacteria with resistance mutations survive antibiotic treatment and pass on that trait, illustrating natural selection acting on variation in a population.
Question 5: Which best describes the electromagnetic spectrum arrangement from lowest to highest energy?
- Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma (Correct answer)
- Gamma, X-ray, ultraviolet, visible, infrared, microwave, radio
- Visible, infrared, ultraviolet, radio, microwave, X-ray, gamma
- Microwave, radio, visible, infrared, X-ray, ultraviolet, gamma
Correct answer: Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma
The electromagnetic spectrum increases in energy with frequency; radio waves have the lowest energy and gamma rays have the highest.
Question 6: A student tests the pH of several liquids and finds one with a pH of 2. How should this liquid be classified?
- Strongly basic
- Weakly basic
- Neutral
- Strongly acidic (Correct answer)
Correct answer: Strongly acidic
A pH of 2 is far below 7 (neutral), indicating a high concentration of hydrogen ions and making the liquid a strong acid.
Question 7: Which best describes the difference between a hypothesis and a theory in science?
- A hypothesis is proven true; a theory is still being tested
- A hypothesis is an untested prediction; a theory is a well-supported explanation backed by extensive evidence (Correct answer)
- A hypothesis applies only to chemistry; a theory applies to all sciences
- A hypothesis and a theory are interchangeable terms in science
Correct answer: A hypothesis is an untested prediction; a theory is a well-supported explanation backed by extensive evidence
A hypothesis is a testable prediction made before experimentation, while a scientific theory is a broad explanation supported by repeated evidence and testing.
FTCE Science 5
Which best explains why planets orbit the Sun in elliptical paths rather than circular ones?