BIOL 101 Quiz 2 V2 | BIOL 101 Principles of
Biology | Actual Q&A with Rationale (BIOL101 Quiz
2) | Liberty University
1. Which of the following statements is a fundamental tenet of the cell theory?
A. All living organisms are composed of one or more cells.
B. Cells can arise spontaneously from non-living matter.
C. Cells are not limited in size by their surface area to volume ratio.
D. Multicellular organisms do not rely on cellular functions.
Correct Answer: A
Explanation: The cell theory is a foundational principle in biology that states all living
things are made of cells. It also posits that the cell is the basic unit of life and that all cells
come from pre-existing cells. This theory was developed through the work of Schwann,
Schleiden, and Virchow during the 19th century.
2. What primary feature distinguishes a eukaryotic cell from a prokaryotic cell?
A. The presence of a cell membrane.
B. The ability to perform protein synthesis.
C. The use of DNA as genetic material.
D. The presence of a membrane-bound nucleus.
Correct Answer: D
,Explanation: Eukaryotic cells are defined by having a nucleus that houses their genetic
material, whereas prokaryotic cells have a nucleoid region. In addition to a nucleus,
eukaryotes possess various membrane-bound organelles such as mitochondria and the
endoplasmic reticulum. This internal compartmentalization allows eukaryotes to be larger
and more complex than their prokaryotic counterparts.
3. In the fluid mosaic model, what is the primary role of phospholipids in the plasma
membrane?
A. Acting as receptors for signaling molecules.
B. Actively transporting ions against their concentration gradient.
C. Providing a hydrophobic barrier that separates the cell from its environment.
D. Providing structural support via the cytoskeleton.
Correct Answer: C
Explanation: Phospholipids form a bilayer where the hydrophobic tails face inward and
the hydrophilic heads face outward. This structure creates a semi-permeable barrier that
regulates the passage of molecules into and out of the cell. The fluid nature of this bilayer
allows proteins to move laterally, facilitating various cellular functions.
4. Which process describes the movement of water across a selectively permeable membrane
from an area of low solute concentration to high solute concentration?
A. Active transport
B. Facilitated diffusion
, C. Osmosis
D. Simple diffusion
Correct Answer: C
Explanation: Osmosis is a specific type of passive transport focusing solely on the
movement of water molecules. Water moves down its own concentration gradient, which
corresponds to moving toward a higher concentration of solutes. This process is vital for
maintaining cellular turgor and fluid balance in both plant and animal cells.
5. What is the main difference between passive transport and active transport?
A. Passive transport requires ATP, while active transport does not.
B. Active transport only occurs in prokaryotic cells.
C. Passive transport only involves the movement of water.
D. Active transport requires energy (ATP) to move substances against a concentration
gradient.
Correct Answer: D
Explanation: Active transport is necessary when a cell needs to move molecules from an
area of low concentration to high concentration. This process requires the expenditure of
cellular energy, typically in the form of ATP. In contrast, passive transport occurs naturally
as molecules move down their concentration gradient without energy input.
Biology | Actual Q&A with Rationale (BIOL101 Quiz
2) | Liberty University
1. Which of the following statements is a fundamental tenet of the cell theory?
A. All living organisms are composed of one or more cells.
B. Cells can arise spontaneously from non-living matter.
C. Cells are not limited in size by their surface area to volume ratio.
D. Multicellular organisms do not rely on cellular functions.
Correct Answer: A
Explanation: The cell theory is a foundational principle in biology that states all living
things are made of cells. It also posits that the cell is the basic unit of life and that all cells
come from pre-existing cells. This theory was developed through the work of Schwann,
Schleiden, and Virchow during the 19th century.
2. What primary feature distinguishes a eukaryotic cell from a prokaryotic cell?
A. The presence of a cell membrane.
B. The ability to perform protein synthesis.
C. The use of DNA as genetic material.
D. The presence of a membrane-bound nucleus.
Correct Answer: D
,Explanation: Eukaryotic cells are defined by having a nucleus that houses their genetic
material, whereas prokaryotic cells have a nucleoid region. In addition to a nucleus,
eukaryotes possess various membrane-bound organelles such as mitochondria and the
endoplasmic reticulum. This internal compartmentalization allows eukaryotes to be larger
and more complex than their prokaryotic counterparts.
3. In the fluid mosaic model, what is the primary role of phospholipids in the plasma
membrane?
A. Acting as receptors for signaling molecules.
B. Actively transporting ions against their concentration gradient.
C. Providing a hydrophobic barrier that separates the cell from its environment.
D. Providing structural support via the cytoskeleton.
Correct Answer: C
Explanation: Phospholipids form a bilayer where the hydrophobic tails face inward and
the hydrophilic heads face outward. This structure creates a semi-permeable barrier that
regulates the passage of molecules into and out of the cell. The fluid nature of this bilayer
allows proteins to move laterally, facilitating various cellular functions.
4. Which process describes the movement of water across a selectively permeable membrane
from an area of low solute concentration to high solute concentration?
A. Active transport
B. Facilitated diffusion
, C. Osmosis
D. Simple diffusion
Correct Answer: C
Explanation: Osmosis is a specific type of passive transport focusing solely on the
movement of water molecules. Water moves down its own concentration gradient, which
corresponds to moving toward a higher concentration of solutes. This process is vital for
maintaining cellular turgor and fluid balance in both plant and animal cells.
5. What is the main difference between passive transport and active transport?
A. Passive transport requires ATP, while active transport does not.
B. Active transport only occurs in prokaryotic cells.
C. Passive transport only involves the movement of water.
D. Active transport requires energy (ATP) to move substances against a concentration
gradient.
Correct Answer: D
Explanation: Active transport is necessary when a cell needs to move molecules from an
area of low concentration to high concentration. This process requires the expenditure of
cellular energy, typically in the form of ATP. In contrast, passive transport occurs naturally
as molecules move down their concentration gradient without energy input.
