WGU C190 Intro to Biology Actual OA Exam |
Complete Test Approved Questions Correct Verified
Answers – Pass Guaranteed - A+ Graded
Scientific Inquiry, Chemistry of Life & Biological Molecules
Q1: A student wants to test if a new fertilizer helps tomato plants grow taller. They plant
two groups of tomatoes: Group A receives the new fertilizer, and Group B receives only
water. Both groups are kept in the same greenhouse with equal sunlight. In this
experiment, which of the following best describes the dependent variable?
A. The type of fertilizer used
B. The amount of water given to the plants
C. The height of the tomato plants
D. The presence of sunlight in the greenhouse
Correct Answer: C
Rationale: The best answer is C because the dependent variable is what the researcher
measures to see if it was affected by the treatment; in this case, it's the plant height
resulting from the fertilizer.
Q2: Which statement correctly distinguishes a scientific theory from a scientific
hypothesis?
A. A theory is a tentative guess, while a hypothesis is a proven fact
B. A hypothesis is an initial explanation that can be tested, while a theory is a
comprehensive, well-supported explanation supported by a vast body of evidence
C. A theory is based on belief, while a hypothesis is based on data
D. A hypothesis describes what happened in an experiment, while a theory predicts
what will happen in the future
Correct Answer: B
Rationale: This is correct because in biology we know that a hypothesis is a starting
point for investigation, whereas a theory is the end result of repeated testing and
confirmation, like the Theory of Evolution.
Q3: Why is water often referred to as the "universal solvent" in biological systems?
A. Because it has a high specific heat, allowing it to dissolve metals easily
B. Because its polar nature allows it to dissolve ionic and polar substances
C. Because it is a nonpolar molecule that mixes with lipids
D. Because it freezes from the top down, allowing solids to dissolve in the ice
Correct Answer: B
,Rationale: This choice is correct because water molecules have a slight positive and
negative charge (polarity) that attracts other charged molecules, pulling them apart and
surrounding them effectively.
Q4: A solution has a pH of 3. How does this compare to a solution with a pH of 5?
A. It is 2 times more acidic
B. It is 100 times more acidic
C. It is 2 times more basic
D. It is 100 times more basic
Correct Answer: B
Rationale: Remember that the pH scale is logarithmic, meaning each whole number
difference represents a tenfold change; therefore, a difference of 2 represents a change
of 10 x 10, or 100 times.
Q5: Which of the following best describes the formation of an ionic bond?
A. Two atoms share a pair of electrons equally
B. One atom transfers an electron to another atom, resulting in oppositely charged ions
that attract
C. A molecule with slight charges attracts another molecule with slight charges
D. Two non-metal atoms share electron pairs in a double bond
Correct Answer: B
Rationale: The best answer is B because ionic bonds specifically involve the transfer of
electrons creating a charged attraction (cation and anion), unlike covalent bonds which
involve sharing.
Q6: Which of the following is a monosaccharide that is a primary source of energy for
human cells?
A. Sucrose
B. Cellulose
C. Glucose
D. Glycogen
Correct Answer: C
Rationale: This query works because glucose is the basic unit of carbohydrates and is
the sugar directly used in cellular respiration to produce ATP, whereas sucrose is a
disaccharide and cellulose/glycogen are polysaccharides.
Q7: You are analyzing a molecule composed of a chain of amino acids. This molecule is
a:
A. Protein
B. Lipid
C. Nucleic Acid
, D. Carbohydrate
Correct Answer: A
Rationale: The best answer is A because proteins are the biological macromolecules
defined by being polymers made up of monomer units called amino acids linked
together by peptide bonds.
Q8: Which of the following types of lipids is the primary component of the cell
membrane?
A. Triglycerides (fats)
B. Phospholipids
C. Steroids
D. Waxes
Correct Answer: B
Rationale: This choice is correct because the cell membrane is made of a phospholipid
bilayer, which creates a stable barrier with a hydrophilic head and hydrophobic tails,
unlike fats or steroids which serve other functions.
Q9: If a DNA strand has the sequence 5'-ATCG-3', what would be the sequence of the
complementary RNA strand?
A. 5'-UAGC-3'
B. 3'-UAGC-5'
C. 5'-TAGC-3'
D. 3'-ATCG-5'
Correct Answer: A
Rationale: This matches the rule that in RNA, Uracil replaces Thymine as the pair for
Adenine, and the strands are antiparallel, so the 5' end pairs with the 3' end of the
complement.
Q10: Scenario: A biology student sets up an experiment to test how different
wavelengths of light affect the rate of photosynthesis in Elodea plants. They place three
plants under red, green, and blue lights respectively, and measure the number of
oxygen bubbles produced per minute. What is the independent variable in this setup?
A. The number of oxygen bubbles produced per minute
B. The species of plant used (Elodea)
C. The different wavelengths (colors) of light
D. The temperature of the water the plants are in
Correct Answer: C
Rationale: The best answer is C because the independent variable is the factor that the
scientist actively changes or manipulates to observe its effect, which here is the color of
the light.
Complete Test Approved Questions Correct Verified
Answers – Pass Guaranteed - A+ Graded
Scientific Inquiry, Chemistry of Life & Biological Molecules
Q1: A student wants to test if a new fertilizer helps tomato plants grow taller. They plant
two groups of tomatoes: Group A receives the new fertilizer, and Group B receives only
water. Both groups are kept in the same greenhouse with equal sunlight. In this
experiment, which of the following best describes the dependent variable?
A. The type of fertilizer used
B. The amount of water given to the plants
C. The height of the tomato plants
D. The presence of sunlight in the greenhouse
Correct Answer: C
Rationale: The best answer is C because the dependent variable is what the researcher
measures to see if it was affected by the treatment; in this case, it's the plant height
resulting from the fertilizer.
Q2: Which statement correctly distinguishes a scientific theory from a scientific
hypothesis?
A. A theory is a tentative guess, while a hypothesis is a proven fact
B. A hypothesis is an initial explanation that can be tested, while a theory is a
comprehensive, well-supported explanation supported by a vast body of evidence
C. A theory is based on belief, while a hypothesis is based on data
D. A hypothesis describes what happened in an experiment, while a theory predicts
what will happen in the future
Correct Answer: B
Rationale: This is correct because in biology we know that a hypothesis is a starting
point for investigation, whereas a theory is the end result of repeated testing and
confirmation, like the Theory of Evolution.
Q3: Why is water often referred to as the "universal solvent" in biological systems?
A. Because it has a high specific heat, allowing it to dissolve metals easily
B. Because its polar nature allows it to dissolve ionic and polar substances
C. Because it is a nonpolar molecule that mixes with lipids
D. Because it freezes from the top down, allowing solids to dissolve in the ice
Correct Answer: B
,Rationale: This choice is correct because water molecules have a slight positive and
negative charge (polarity) that attracts other charged molecules, pulling them apart and
surrounding them effectively.
Q4: A solution has a pH of 3. How does this compare to a solution with a pH of 5?
A. It is 2 times more acidic
B. It is 100 times more acidic
C. It is 2 times more basic
D. It is 100 times more basic
Correct Answer: B
Rationale: Remember that the pH scale is logarithmic, meaning each whole number
difference represents a tenfold change; therefore, a difference of 2 represents a change
of 10 x 10, or 100 times.
Q5: Which of the following best describes the formation of an ionic bond?
A. Two atoms share a pair of electrons equally
B. One atom transfers an electron to another atom, resulting in oppositely charged ions
that attract
C. A molecule with slight charges attracts another molecule with slight charges
D. Two non-metal atoms share electron pairs in a double bond
Correct Answer: B
Rationale: The best answer is B because ionic bonds specifically involve the transfer of
electrons creating a charged attraction (cation and anion), unlike covalent bonds which
involve sharing.
Q6: Which of the following is a monosaccharide that is a primary source of energy for
human cells?
A. Sucrose
B. Cellulose
C. Glucose
D. Glycogen
Correct Answer: C
Rationale: This query works because glucose is the basic unit of carbohydrates and is
the sugar directly used in cellular respiration to produce ATP, whereas sucrose is a
disaccharide and cellulose/glycogen are polysaccharides.
Q7: You are analyzing a molecule composed of a chain of amino acids. This molecule is
a:
A. Protein
B. Lipid
C. Nucleic Acid
, D. Carbohydrate
Correct Answer: A
Rationale: The best answer is A because proteins are the biological macromolecules
defined by being polymers made up of monomer units called amino acids linked
together by peptide bonds.
Q8: Which of the following types of lipids is the primary component of the cell
membrane?
A. Triglycerides (fats)
B. Phospholipids
C. Steroids
D. Waxes
Correct Answer: B
Rationale: This choice is correct because the cell membrane is made of a phospholipid
bilayer, which creates a stable barrier with a hydrophilic head and hydrophobic tails,
unlike fats or steroids which serve other functions.
Q9: If a DNA strand has the sequence 5'-ATCG-3', what would be the sequence of the
complementary RNA strand?
A. 5'-UAGC-3'
B. 3'-UAGC-5'
C. 5'-TAGC-3'
D. 3'-ATCG-5'
Correct Answer: A
Rationale: This matches the rule that in RNA, Uracil replaces Thymine as the pair for
Adenine, and the strands are antiparallel, so the 5' end pairs with the 3' end of the
complement.
Q10: Scenario: A biology student sets up an experiment to test how different
wavelengths of light affect the rate of photosynthesis in Elodea plants. They place three
plants under red, green, and blue lights respectively, and measure the number of
oxygen bubbles produced per minute. What is the independent variable in this setup?
A. The number of oxygen bubbles produced per minute
B. The species of plant used (Elodea)
C. The different wavelengths (colors) of light
D. The temperature of the water the plants are in
Correct Answer: C
Rationale: The best answer is C because the independent variable is the factor that the
scientist actively changes or manipulates to observe its effect, which here is the color of
the light.
