DCCC BIO 150 Lab Practical 1 Exam 2026/2027 – 200
Practice Questions & Answers with Detailed Rationales |
Latest Study Guide
Section 1: Laboratory Safety, Equipment & Scientific Method — Questions 1–25
1. Which piece of equipment is primarily used to measure liquid volume accurately in
a biology laboratory?
A. Beaker
B. Graduated cylinder
C. Erlenmeyer flask
D. Petri dish
Correct Answer: B
Rationale: A graduated cylinder is designed to measure liquid volume with greater accuracy
than a beaker or flask.
2. When reading the volume of a liquid in a graduated cylinder, the measurement
should be taken at:
A. The top of the container
B. Eye level with the meniscus
,C. The bottom of the cylinder
D. Any convenient angle
Correct Answer: B
Rationale: Viewing the meniscus at eye level minimizes parallax error.
3. Which laboratory instrument is best suited for transferring a small, precise volume
of liquid?
A. Micropipette
B. Beaker
C. Watch glass
D. Evaporating dish
Correct Answer: A
Rationale: Micropipettes are designed to accurately measure and transfer very small liquid
volumes.
4. A micropipette labeled P1000 is generally designed to measure volumes in the
range of:
A. 0.1–1 µL
B. 10–100 µL
C. 100–1000 µL
D. 1000–10,000 µL
Correct Answer: C
Rationale: A P1000 is commonly used for volumes from approximately 100 to 1000 µL.
,5. Which item should be worn to protect the eyes during laboratory activities
involving chemicals?
A. Face mask
B. Safety goggles
C. Gloves only
D. Apron only
Correct Answer: B
Rationale: Safety goggles protect the eyes from chemical splashes and laboratory hazards.
6. If a chemical spills on your skin, the first appropriate response is generally to:
A. Wipe it off with a paper towel
B. Ignore it if the amount is small
C. Rinse the affected area thoroughly with water
D. Apply another chemical to neutralize it
Correct Answer: C
Rationale: Promptly flushing the affected area with water helps remove and dilute the
chemical.
7. Which symbol indicates a substance may be corrosive?
A. Flame
B. Test tube damaging a hand or metal
, C. Gas cylinder
D. Skull and crossbones
Correct Answer: B
Rationale: The corrosion pictogram indicates substances that can damage tissue or corrode
metals.
8. What is the primary purpose of a control group in an experiment?
A. To increase experimental errors
B. To provide a comparison for the experimental treatment
C. To eliminate the dependent variable
D. To guarantee the hypothesis is correct
Correct Answer: B
Rationale: A control provides a baseline against which experimental results can be
compared.
9. The variable deliberately changed by a researcher is called the:
A. Dependent variable
B. Controlled variable
C. Independent variable
D. Responding constant
Correct Answer: C
Rationale: The independent variable is intentionally manipulated by the researcher.
Practice Questions & Answers with Detailed Rationales |
Latest Study Guide
Section 1: Laboratory Safety, Equipment & Scientific Method — Questions 1–25
1. Which piece of equipment is primarily used to measure liquid volume accurately in
a biology laboratory?
A. Beaker
B. Graduated cylinder
C. Erlenmeyer flask
D. Petri dish
Correct Answer: B
Rationale: A graduated cylinder is designed to measure liquid volume with greater accuracy
than a beaker or flask.
2. When reading the volume of a liquid in a graduated cylinder, the measurement
should be taken at:
A. The top of the container
B. Eye level with the meniscus
,C. The bottom of the cylinder
D. Any convenient angle
Correct Answer: B
Rationale: Viewing the meniscus at eye level minimizes parallax error.
3. Which laboratory instrument is best suited for transferring a small, precise volume
of liquid?
A. Micropipette
B. Beaker
C. Watch glass
D. Evaporating dish
Correct Answer: A
Rationale: Micropipettes are designed to accurately measure and transfer very small liquid
volumes.
4. A micropipette labeled P1000 is generally designed to measure volumes in the
range of:
A. 0.1–1 µL
B. 10–100 µL
C. 100–1000 µL
D. 1000–10,000 µL
Correct Answer: C
Rationale: A P1000 is commonly used for volumes from approximately 100 to 1000 µL.
,5. Which item should be worn to protect the eyes during laboratory activities
involving chemicals?
A. Face mask
B. Safety goggles
C. Gloves only
D. Apron only
Correct Answer: B
Rationale: Safety goggles protect the eyes from chemical splashes and laboratory hazards.
6. If a chemical spills on your skin, the first appropriate response is generally to:
A. Wipe it off with a paper towel
B. Ignore it if the amount is small
C. Rinse the affected area thoroughly with water
D. Apply another chemical to neutralize it
Correct Answer: C
Rationale: Promptly flushing the affected area with water helps remove and dilute the
chemical.
7. Which symbol indicates a substance may be corrosive?
A. Flame
B. Test tube damaging a hand or metal
, C. Gas cylinder
D. Skull and crossbones
Correct Answer: B
Rationale: The corrosion pictogram indicates substances that can damage tissue or corrode
metals.
8. What is the primary purpose of a control group in an experiment?
A. To increase experimental errors
B. To provide a comparison for the experimental treatment
C. To eliminate the dependent variable
D. To guarantee the hypothesis is correct
Correct Answer: B
Rationale: A control provides a baseline against which experimental results can be
compared.
9. The variable deliberately changed by a researcher is called the:
A. Dependent variable
B. Controlled variable
C. Independent variable
D. Responding constant
Correct Answer: C
Rationale: The independent variable is intentionally manipulated by the researcher.
