ASVAB GENERAL SCIENCE (GS) PRACTICE EXAMINATION
STUDY GUIDE | LATEST UPDATE 2026/2027 | ACTUAL EXAM |
PRACTICE QUESTIONS AND ANSWERS | EXAM REVIEW |
100% CORRECT ANSWERS | LATEST SOLUTION.
1: Which of the following is the correct order of the scientific method?
A) Hypothesis, observation, experiment, conclusion, theory
B) Observation, hypothesis, experiment, conclusion, theory
C) Experiment, hypothesis, observation, theory, conclusion
D) Conclusion, theory, observation, hypothesis, experiment
Correct Answer: B
The scientific method begins with observation, followed by forming a hypothesis, conducting
experiments to test the hypothesis, drawing conclusions from the data, and eventually
developing a theory if the hypothesis is repeatedly supported. Option A incorrectly places
hypothesis before observation. Options C and D reverse or scramble the logical sequence.
2: Which organelle is responsible for producing ATP through cellular respiration?
A) Nucleus
B) Ribosome
C) Mitochondrion
D) Golgi apparatus
Correct Answer: C
Mitochondria are the powerhouses of the cell, generating ATP via aerobic respiration. The
,nucleus stores genetic material, ribosomes synthesize proteins, and the Golgi apparatus
modifies and packages proteins.
3: What is the primary function of red blood cells?
A) Fighting infection
B) Clotting blood
C) Transporting oxygen
D) Producing antibodies
Correct Answer: C
Red blood cells contain hemoglobin, which binds oxygen in the lungs and delivers it to tissues.
White blood cells fight infection and produce antibodies, while platelets are responsible for
blood clotting.
4: Which of the following is a chemical change?
A) Melting ice
B) Boiling water
C) Burning wood
D) Dissolving sugar in water
Correct Answer: C
Burning wood produces new substances (ash, carbon dioxide, water vapor) and cannot be
reversed by physical means, making it a chemical change. Melting, boiling, and dissolving are
physical changes because the substance's chemical identity remains unchanged.
5: What is the basic unit of heredity?
A) Chromosome
B) Gene
,C) Protein
D) Nucleotide
Correct Answer: B
Genes are the fundamental units of heredity, consisting of DNA sequences that code for
proteins. Chromosomes are structures containing many genes. Nucleotides are the building
blocks of DNA, and proteins are gene products.
Page 2
6: Which planet in our solar system has the most moons?
A) Earth
B) Mars
C) Jupiter
D) Saturn
Correct Answer: D
As of current astronomical data, Saturn has over 140 known moons, surpassing Jupiter's
count of about 95. Earth has one moon and Mars has two small moons. The question requires
the most up-to-date count, and Saturn currently holds the record.
7: What is the normal pH of human blood?
A) 6.8
B) 7.0
C) 7.4
D) 7.8
Correct Answer: C
Human blood is slightly alkaline with a normal pH range of approximately 7.35 to 7.45, with
7.4 being the average. Values below 7.35 indicate acidosis and above 7.45 indicate alkalosis.
Options A, B, and D fall outside the normal physiological range.
, 8: Which of the following is a renewable energy source?
A) Coal
B) Natural gas
C) Solar power
D) Petroleum
Correct Answer: C
Solar power is renewable because it is derived from the sun's radiation, which is continuously
replenished. Coal, natural gas, and petroleum are fossil fuels formed over millions of years
and are nonrenewable on human timescales.
9: The process by which plants convert sunlight into chemical energy is called:
A) Respiration
B) Transpiration
C) Photosynthesis
D) Fermentation
Correct Answer: C
Photosynthesis uses chlorophyll, sunlight, water, and carbon dioxide to produce glucose and
oxygen. Respiration releases energy from glucose, transpiration is water loss through leaves,
and fermentation is anaerobic energy production.
10: What is the most abundant gas in Earth's atmosphere?
A) Oxygen
B) Carbon dioxide
C) Nitrogen
D) Argon
STUDY GUIDE | LATEST UPDATE 2026/2027 | ACTUAL EXAM |
PRACTICE QUESTIONS AND ANSWERS | EXAM REVIEW |
100% CORRECT ANSWERS | LATEST SOLUTION.
1: Which of the following is the correct order of the scientific method?
A) Hypothesis, observation, experiment, conclusion, theory
B) Observation, hypothesis, experiment, conclusion, theory
C) Experiment, hypothesis, observation, theory, conclusion
D) Conclusion, theory, observation, hypothesis, experiment
Correct Answer: B
The scientific method begins with observation, followed by forming a hypothesis, conducting
experiments to test the hypothesis, drawing conclusions from the data, and eventually
developing a theory if the hypothesis is repeatedly supported. Option A incorrectly places
hypothesis before observation. Options C and D reverse or scramble the logical sequence.
2: Which organelle is responsible for producing ATP through cellular respiration?
A) Nucleus
B) Ribosome
C) Mitochondrion
D) Golgi apparatus
Correct Answer: C
Mitochondria are the powerhouses of the cell, generating ATP via aerobic respiration. The
,nucleus stores genetic material, ribosomes synthesize proteins, and the Golgi apparatus
modifies and packages proteins.
3: What is the primary function of red blood cells?
A) Fighting infection
B) Clotting blood
C) Transporting oxygen
D) Producing antibodies
Correct Answer: C
Red blood cells contain hemoglobin, which binds oxygen in the lungs and delivers it to tissues.
White blood cells fight infection and produce antibodies, while platelets are responsible for
blood clotting.
4: Which of the following is a chemical change?
A) Melting ice
B) Boiling water
C) Burning wood
D) Dissolving sugar in water
Correct Answer: C
Burning wood produces new substances (ash, carbon dioxide, water vapor) and cannot be
reversed by physical means, making it a chemical change. Melting, boiling, and dissolving are
physical changes because the substance's chemical identity remains unchanged.
5: What is the basic unit of heredity?
A) Chromosome
B) Gene
,C) Protein
D) Nucleotide
Correct Answer: B
Genes are the fundamental units of heredity, consisting of DNA sequences that code for
proteins. Chromosomes are structures containing many genes. Nucleotides are the building
blocks of DNA, and proteins are gene products.
Page 2
6: Which planet in our solar system has the most moons?
A) Earth
B) Mars
C) Jupiter
D) Saturn
Correct Answer: D
As of current astronomical data, Saturn has over 140 known moons, surpassing Jupiter's
count of about 95. Earth has one moon and Mars has two small moons. The question requires
the most up-to-date count, and Saturn currently holds the record.
7: What is the normal pH of human blood?
A) 6.8
B) 7.0
C) 7.4
D) 7.8
Correct Answer: C
Human blood is slightly alkaline with a normal pH range of approximately 7.35 to 7.45, with
7.4 being the average. Values below 7.35 indicate acidosis and above 7.45 indicate alkalosis.
Options A, B, and D fall outside the normal physiological range.
, 8: Which of the following is a renewable energy source?
A) Coal
B) Natural gas
C) Solar power
D) Petroleum
Correct Answer: C
Solar power is renewable because it is derived from the sun's radiation, which is continuously
replenished. Coal, natural gas, and petroleum are fossil fuels formed over millions of years
and are nonrenewable on human timescales.
9: The process by which plants convert sunlight into chemical energy is called:
A) Respiration
B) Transpiration
C) Photosynthesis
D) Fermentation
Correct Answer: C
Photosynthesis uses chlorophyll, sunlight, water, and carbon dioxide to produce glucose and
oxygen. Respiration releases energy from glucose, transpiration is water loss through leaves,
and fermentation is anaerobic energy production.
10: What is the most abundant gas in Earth's atmosphere?
A) Oxygen
B) Carbon dioxide
C) Nitrogen
D) Argon
