WGU C190 Intro to Biology Practice Test Questions | 170+
Questions with 100% Correct Answers Plus
Rationales/Grade A+ Assured
Question 1
Which of the following is considered the basic unit of all known living things?
A) Atom
B) Molecule
C) Cell
D) Tissue
E) Organ
Correct Answer: C) Cell
Rationale: The cell is the fundamental structural and functional unit
of all known living organisms.
Question 2
Which organelle is responsible for generating most of the cell's supply of
adenosine triphosphate (ATP), used as a source of chemical energy?
A) Nucleus
B) Ribosome
C) Endoplasmic Reticulum
D) Mitochondria
E) Golgi Apparatus
Correct Answer: D) Mitochondria
Rationale: Mitochondria are often referred to as the "powerhouses"
of the cell because they produce ATP through cellular respiration.
Question 3
Which of the following describes a prokaryotic cell?
A) Contains a nucleus and membrane-bound organelles.
B) Lacks a nucleus and membrane-bound organelles.
C) Always multicellular.
D) Found only in plants.
E) Always larger than eukaryotic cells.
Correct Answer: B) Lacks a nucleus and membrane-bound organelles.
,Rationale: Prokaryotic cells (bacteria and archaea) are simpler in
structure than eukaryotic cells, lacking a true nucleus and other
membrane-enclosed organelles.
Question 4
What is the primary function of DNA (deoxyribonucleic acid) in living
organisms?
A) To transport oxygen.
B) To store and transmit genetic information.
C) To provide immediate energy.
D) To build proteins.
E) To regulate body temperature.
Correct Answer: B) To store and transmit genetic information.
Rationale: DNA carries the genetic instructions used in the growth,
development, functioning, and reproduction of all known living
organisms and many viruses.
Question 5
Which of the following is the process by which plants convert light energy
into chemical energy (glucose)?
A) Cellular Respiration
B) Fermentation
C) Photosynthesis
D) Transpiration
E) Glycolysis
Correct Answer: C) Photosynthesis
Rationale: Photosynthesis is the fundamental process by which green
plants, algae, and some bacteria convert sunlight into glucose,
releasing oxygen as a byproduct.
Question 6
What are the four main macromolecules found in living organisms?
A) Oxygen, Carbon, Hydrogen, Nitrogen
,B) Water, Salt, Sugar, Protein
C) Carbohydrates, Lipids, Proteins, Nucleic Acids
D) Vitamins, Minerals, Fiber, Water
E) DNA, RNA, ATP, ADP
Correct Answer: C) Carbohydrates, Lipids, Proteins, Nucleic Acids
Rationale: These are the four major classes of organic molecules
essential for life, performing a vast array of functions within cells.
Question 7
Which organelle is responsible for protein synthesis?
A) Nucleus
B) Mitochondria
C) Ribosome
D) Lysosome
E) Vacuole
Correct Answer: C) Ribosome
Rationale: Ribosomes are the cellular machines responsible for
translating messenger RNA (mRNA) into proteins.
Question 8
What does "homeostasis" refer to in biology?
A) The process of evolution.
B) The maintenance of a stable internal environment in an organism.
C) The growth of an organism.
D) The reproduction of an organism.
E) The constant change in an organism's internal conditions.
Correct Answer: B) The maintenance of a stable internal environment
in an organism.
Rationale: Homeostasis involves various regulatory mechanisms
(e.g., temperature regulation, blood glucose control) that keep
internal conditions relatively constant despite external changes.
, Question 9
Which of the following is the process of cell division that results in two
daughter cells each having the same number and kind of chromosomes as
the parent nucleus?
A) Meiosis
B) Fertilization
C) Mitosis
D) Transcription
E) Translation
Correct Answer: C) Mitosis
Rationale: Mitosis is the process of somatic cell division, resulting in
two genetically identical daughter cells, crucial for growth and
repair.
Question 10
What is the primary product of photosynthesis?
A) Carbon dioxide and water
B) Oxygen and glucose
C) Nitrogen and ammonia
D) ATP and heat
E) Lactic acid
Correct Answer: B) Oxygen and glucose
Rationale: Photosynthesis uses carbon dioxide, water, and light
energy to produce glucose (sugar) and oxygen.
Question 11
Which type of organism obtains energy by consuming other organisms?
A) Autotroph
B) Producer
C) Heterotroph
D) Chemotroph
E) Phototroph
Questions with 100% Correct Answers Plus
Rationales/Grade A+ Assured
Question 1
Which of the following is considered the basic unit of all known living things?
A) Atom
B) Molecule
C) Cell
D) Tissue
E) Organ
Correct Answer: C) Cell
Rationale: The cell is the fundamental structural and functional unit
of all known living organisms.
Question 2
Which organelle is responsible for generating most of the cell's supply of
adenosine triphosphate (ATP), used as a source of chemical energy?
A) Nucleus
B) Ribosome
C) Endoplasmic Reticulum
D) Mitochondria
E) Golgi Apparatus
Correct Answer: D) Mitochondria
Rationale: Mitochondria are often referred to as the "powerhouses"
of the cell because they produce ATP through cellular respiration.
Question 3
Which of the following describes a prokaryotic cell?
A) Contains a nucleus and membrane-bound organelles.
B) Lacks a nucleus and membrane-bound organelles.
C) Always multicellular.
D) Found only in plants.
E) Always larger than eukaryotic cells.
Correct Answer: B) Lacks a nucleus and membrane-bound organelles.
,Rationale: Prokaryotic cells (bacteria and archaea) are simpler in
structure than eukaryotic cells, lacking a true nucleus and other
membrane-enclosed organelles.
Question 4
What is the primary function of DNA (deoxyribonucleic acid) in living
organisms?
A) To transport oxygen.
B) To store and transmit genetic information.
C) To provide immediate energy.
D) To build proteins.
E) To regulate body temperature.
Correct Answer: B) To store and transmit genetic information.
Rationale: DNA carries the genetic instructions used in the growth,
development, functioning, and reproduction of all known living
organisms and many viruses.
Question 5
Which of the following is the process by which plants convert light energy
into chemical energy (glucose)?
A) Cellular Respiration
B) Fermentation
C) Photosynthesis
D) Transpiration
E) Glycolysis
Correct Answer: C) Photosynthesis
Rationale: Photosynthesis is the fundamental process by which green
plants, algae, and some bacteria convert sunlight into glucose,
releasing oxygen as a byproduct.
Question 6
What are the four main macromolecules found in living organisms?
A) Oxygen, Carbon, Hydrogen, Nitrogen
,B) Water, Salt, Sugar, Protein
C) Carbohydrates, Lipids, Proteins, Nucleic Acids
D) Vitamins, Minerals, Fiber, Water
E) DNA, RNA, ATP, ADP
Correct Answer: C) Carbohydrates, Lipids, Proteins, Nucleic Acids
Rationale: These are the four major classes of organic molecules
essential for life, performing a vast array of functions within cells.
Question 7
Which organelle is responsible for protein synthesis?
A) Nucleus
B) Mitochondria
C) Ribosome
D) Lysosome
E) Vacuole
Correct Answer: C) Ribosome
Rationale: Ribosomes are the cellular machines responsible for
translating messenger RNA (mRNA) into proteins.
Question 8
What does "homeostasis" refer to in biology?
A) The process of evolution.
B) The maintenance of a stable internal environment in an organism.
C) The growth of an organism.
D) The reproduction of an organism.
E) The constant change in an organism's internal conditions.
Correct Answer: B) The maintenance of a stable internal environment
in an organism.
Rationale: Homeostasis involves various regulatory mechanisms
(e.g., temperature regulation, blood glucose control) that keep
internal conditions relatively constant despite external changes.
, Question 9
Which of the following is the process of cell division that results in two
daughter cells each having the same number and kind of chromosomes as
the parent nucleus?
A) Meiosis
B) Fertilization
C) Mitosis
D) Transcription
E) Translation
Correct Answer: C) Mitosis
Rationale: Mitosis is the process of somatic cell division, resulting in
two genetically identical daughter cells, crucial for growth and
repair.
Question 10
What is the primary product of photosynthesis?
A) Carbon dioxide and water
B) Oxygen and glucose
C) Nitrogen and ammonia
D) ATP and heat
E) Lactic acid
Correct Answer: B) Oxygen and glucose
Rationale: Photosynthesis uses carbon dioxide, water, and light
energy to produce glucose (sugar) and oxygen.
Question 11
Which type of organism obtains energy by consuming other organisms?
A) Autotroph
B) Producer
C) Heterotroph
D) Chemotroph
E) Phototroph
