BIO 189 Final Exam: Fundamentals of Biology V2 - Arizona
College Updated and Latest Questions and Correct
Answers with Rationale
1. Which of the following statements is a core principle of the Cell Theory?
A. All living organisms are composed of one or more cells.
B. Cells arise spontaneously from non-living matter.
C. Energy flows only between multicellular organisms.
D. Organelles are the smallest units of life.
Ans: A
Explanation: The cell theory states that all living things are composed of cells. It also establishes that the
cell is the basic unit of life. All cells come from pre-existing cells through division. This theory is a
fundamental concept in modern biology. It refutes the idea of spontaneous generation which was once
widely believed.
2. Water’s ability to form hydrogen bonds is primarily due to what property?
A. Its nonpolar covalent bonds.
B. The presence of ionic bonds between molecules.
C. Its high molecular weight.
D. The electronegativity of the oxygen atom.
Ans: D
Explanation: Oxygen is much more electronegative than hydrogen in a water molecule. This creates a
partial negative charge on the oxygen and partial positive charges on the hydrogens. These partial
,charges allow water molecules to attract one another. This attraction is what defines a hydrogen bond.
Such bonds are responsible for water’s unique properties like high surface tension.
3. What is the primary function of the mitochondria in eukaryotic cells?
A. Protein synthesis and modification.
B. Production of ATP through cellular respiration.
C. Photosynthesis and glucose production.
D. Storage of genetic information.
Ans: B
Explanation: Mitochondria are often referred to as the powerhouses of the cell. They convert chemical
energy from food into a form the cell can use. This process involves the consumption of oxygen to
produce ATP. ATP serves as the primary energy currency for cellular work. These organelles possess
their own DNA and double membranes.
4. During which phase of the cell cycle is DNA replicated?
A. G1 phase
B. S phase
C. G2 phase
D. M phase
Ans: B
Explanation: The S phase stands for the synthesis phase of the cell cycle. During this time, the cell copies
its entire genome accurately. This ensures that daughter cells receive a complete set of instructions.
, Without this step, mitosis would not result in genetically identical cells. It occurs within interphase
between the growth phases.
5. Enzymes speed up chemical reactions by doing what?
A. Lowering the activation energy required.
B. Providing extra energy to the reactants.
C. Increasing the temperature of the reaction.
D. Changing the equilibrium of the reaction.
Ans: A
Explanation: Enzymes act as biological catalysts to facilitate metabolic pathways. They lower the energy
barrier needed for a reaction to begin. By binding to substrates, they stabilize transition states. This
allows reactions to occur faster at physiological temperatures. The enzyme itself is not consumed during
the process.
6. Which molecule is the main component of the cell membrane’s bilayer?
A. Phospholipids
B. Cholesterol
C. Triglycerides
D. Glycoproteins
Ans: A
Explanation: Phospholipids possess both a hydrophilic head and two hydrophobic tails. In an aqueous
environment, they spontaneously form a bilayer structure. This bilayer creates a semi-permeable barrier
College Updated and Latest Questions and Correct
Answers with Rationale
1. Which of the following statements is a core principle of the Cell Theory?
A. All living organisms are composed of one or more cells.
B. Cells arise spontaneously from non-living matter.
C. Energy flows only between multicellular organisms.
D. Organelles are the smallest units of life.
Ans: A
Explanation: The cell theory states that all living things are composed of cells. It also establishes that the
cell is the basic unit of life. All cells come from pre-existing cells through division. This theory is a
fundamental concept in modern biology. It refutes the idea of spontaneous generation which was once
widely believed.
2. Water’s ability to form hydrogen bonds is primarily due to what property?
A. Its nonpolar covalent bonds.
B. The presence of ionic bonds between molecules.
C. Its high molecular weight.
D. The electronegativity of the oxygen atom.
Ans: D
Explanation: Oxygen is much more electronegative than hydrogen in a water molecule. This creates a
partial negative charge on the oxygen and partial positive charges on the hydrogens. These partial
,charges allow water molecules to attract one another. This attraction is what defines a hydrogen bond.
Such bonds are responsible for water’s unique properties like high surface tension.
3. What is the primary function of the mitochondria in eukaryotic cells?
A. Protein synthesis and modification.
B. Production of ATP through cellular respiration.
C. Photosynthesis and glucose production.
D. Storage of genetic information.
Ans: B
Explanation: Mitochondria are often referred to as the powerhouses of the cell. They convert chemical
energy from food into a form the cell can use. This process involves the consumption of oxygen to
produce ATP. ATP serves as the primary energy currency for cellular work. These organelles possess
their own DNA and double membranes.
4. During which phase of the cell cycle is DNA replicated?
A. G1 phase
B. S phase
C. G2 phase
D. M phase
Ans: B
Explanation: The S phase stands for the synthesis phase of the cell cycle. During this time, the cell copies
its entire genome accurately. This ensures that daughter cells receive a complete set of instructions.
, Without this step, mitosis would not result in genetically identical cells. It occurs within interphase
between the growth phases.
5. Enzymes speed up chemical reactions by doing what?
A. Lowering the activation energy required.
B. Providing extra energy to the reactants.
C. Increasing the temperature of the reaction.
D. Changing the equilibrium of the reaction.
Ans: A
Explanation: Enzymes act as biological catalysts to facilitate metabolic pathways. They lower the energy
barrier needed for a reaction to begin. By binding to substrates, they stabilize transition states. This
allows reactions to occur faster at physiological temperatures. The enzyme itself is not consumed during
the process.
6. Which molecule is the main component of the cell membrane’s bilayer?
A. Phospholipids
B. Cholesterol
C. Triglycerides
D. Glycoproteins
Ans: A
Explanation: Phospholipids possess both a hydrophilic head and two hydrophobic tails. In an aqueous
environment, they spontaneously form a bilayer structure. This bilayer creates a semi-permeable barrier
