LEVEL 1 BASIC SCIENCE — PRACTICE
Exam Questions With Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the basic unit of life?
A. Atom
B. Cell
C. Tissue
D. Organ
Answer: B) Cell
Rationale: The cell is the smallest structural and functional unit of all
living organisms.
2. Which organ pumps blood in the human body?
A. Brain
B. Liver
C. Heart
D. Kidney
Answer: C) Heart
Rationale: The heart is a muscular organ that pumps blood
throughout the body via the circulatory system.
,3. Which gas do humans need to breathe?
A. Carbon dioxide
B. Oxygen
C. Nitrogen
D. Hydrogen
Answer: B) Oxygen
Rationale: Oxygen is required for cellular respiration to produce
energy in the body.
4. What is the boiling point of water at sea level?
A. 0°C
B. 50°C
C. 100°C
D. 150°C
Answer: C) 100°C
Rationale: Water boils at 100°C under normal atmospheric pressure.
5. Which planet is known as the Red Planet?
A. Earth
B. Mars
C. Venus
D. Jupiter
,Answer: B) Mars
Rationale: Mars appears red due to iron oxide (rust) on its surface.
6. What is the main source of energy for Earth?
A. Moon
B. Sun
C. Wind
D. Volcanoes
Answer: B) Sun
Rationale: The Sun provides heat and light energy essential for life on
Earth.
7. Which organ helps in breathing?
A. Liver
B. Lungs
C. Stomach
D. Heart
Answer: B) Lungs
Rationale: The lungs are responsible for gas exchange, taking in
oxygen and removing carbon dioxide.
8. What do plants need for photosynthesis?
A. Oxygen and sugar
B. Water, sunlight, and carbon dioxide
, C. Soil only
D. Nitrogen only
Answer: B) Water, sunlight, and carbon dioxide
Rationale: These are the raw materials plants use to produce food
through photosynthesis.
9. What is the freezing point of water?
A. 10°C
B. 0°C
C. -10°C
D. 100°C
Answer: B) 0°C
Rationale: Water freezes at 0°C under normal atmospheric pressure.
10. Which part of the plant absorbs water from soil?
A. Leaves
B. Stem
C. Roots
D. Flowers
Answer: C) Roots
Rationale: Roots absorb water and nutrients from the soil for plant
growth.
11. What is H2O commonly known as?
Exam Questions With Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the basic unit of life?
A. Atom
B. Cell
C. Tissue
D. Organ
Answer: B) Cell
Rationale: The cell is the smallest structural and functional unit of all
living organisms.
2. Which organ pumps blood in the human body?
A. Brain
B. Liver
C. Heart
D. Kidney
Answer: C) Heart
Rationale: The heart is a muscular organ that pumps blood
throughout the body via the circulatory system.
,3. Which gas do humans need to breathe?
A. Carbon dioxide
B. Oxygen
C. Nitrogen
D. Hydrogen
Answer: B) Oxygen
Rationale: Oxygen is required for cellular respiration to produce
energy in the body.
4. What is the boiling point of water at sea level?
A. 0°C
B. 50°C
C. 100°C
D. 150°C
Answer: C) 100°C
Rationale: Water boils at 100°C under normal atmospheric pressure.
5. Which planet is known as the Red Planet?
A. Earth
B. Mars
C. Venus
D. Jupiter
,Answer: B) Mars
Rationale: Mars appears red due to iron oxide (rust) on its surface.
6. What is the main source of energy for Earth?
A. Moon
B. Sun
C. Wind
D. Volcanoes
Answer: B) Sun
Rationale: The Sun provides heat and light energy essential for life on
Earth.
7. Which organ helps in breathing?
A. Liver
B. Lungs
C. Stomach
D. Heart
Answer: B) Lungs
Rationale: The lungs are responsible for gas exchange, taking in
oxygen and removing carbon dioxide.
8. What do plants need for photosynthesis?
A. Oxygen and sugar
B. Water, sunlight, and carbon dioxide
, C. Soil only
D. Nitrogen only
Answer: B) Water, sunlight, and carbon dioxide
Rationale: These are the raw materials plants use to produce food
through photosynthesis.
9. What is the freezing point of water?
A. 10°C
B. 0°C
C. -10°C
D. 100°C
Answer: B) 0°C
Rationale: Water freezes at 0°C under normal atmospheric pressure.
10. Which part of the plant absorbs water from soil?
A. Leaves
B. Stem
C. Roots
D. Flowers
Answer: C) Roots
Rationale: Roots absorb water and nutrients from the soil for plant
growth.
11. What is H2O commonly known as?
