CELL MEMBRANE STRUCTURE TRANSPORT AND
EUKARYOTIC CELL COMPONENTS STUDY GUIDE // A+
GRADED PRESENTATION // MEMBRANE DYNAMICS
ORGANELLE FUNCTIONS CELLULAR TRANSPORT
PROCESSES AND PHYSIOLOGICAL REGULATION FOR
STUDENT MASTERY // ACADEMIC YEAR 2025/2026
What is the primary function of the plasma membrane?
To serve as a barrier between the interior and exterior of the cell, acting as
a selective barrier.
What is the structure of the plasma membrane composed of?
A phospholipid bilayer with embedded proteins.
What model describes the structure of the plasma membrane?
The fluid mosaic model.
What are the two major types of membrane proteins?
Integral proteins and peripheral proteins.
What does selective permeability mean in the context of biological
membranes?
Some substances can pass through the membrane while others cannot.
What is passive transport?
The movement of molecules across the membrane without the use of
energy, moving with their concentration gradient.
What is active transport?
The movement of molecules across the membrane against their
concentration gradient, using energy typically in the form of ATP.
What is a concentration gradient?
, The difference in concentration of a substance across a membrane.
What is osmosis?
The diffusion of water across a selectively permeable membrane.
What do isotonic, hypotonic, and hypertonic mean?
Isotonic: equal concentration; Hypotonic: lower concentration outside the
cell; Hypertonic: higher concentration outside the cell.
How do large molecules typically cross the plasma membrane?
Through vesicular transport mechanisms.
What is facilitated diffusion?
The process of transporting ions and large polar molecules across the
membrane via integral membrane proteins.
What is the role of channel proteins in facilitated diffusion?
They provide a central pore that allows specific ions or molecules to pass
through the membrane.
What is the membrane potential?
The charge imbalance across a membrane, typically measured at around -
70 mV in animal cells.
What factors affect diffusion rates across membranes?
Diameter of the transported molecules, temperature of the solution, and the
electrochemical gradient.
What is the difference between simple diffusion and facilitated diffusion?
Simple diffusion does not require proteins and occurs with small neutral
molecules, while facilitated diffusion requires membrane proteins for polar
and charged molecules.
What is the significance of the asymmetry of biological membranes?
Asymmetry affects the orientation of integral proteins and the distribution of
glycosylation on proteins.
EUKARYOTIC CELL COMPONENTS STUDY GUIDE // A+
GRADED PRESENTATION // MEMBRANE DYNAMICS
ORGANELLE FUNCTIONS CELLULAR TRANSPORT
PROCESSES AND PHYSIOLOGICAL REGULATION FOR
STUDENT MASTERY // ACADEMIC YEAR 2025/2026
What is the primary function of the plasma membrane?
To serve as a barrier between the interior and exterior of the cell, acting as
a selective barrier.
What is the structure of the plasma membrane composed of?
A phospholipid bilayer with embedded proteins.
What model describes the structure of the plasma membrane?
The fluid mosaic model.
What are the two major types of membrane proteins?
Integral proteins and peripheral proteins.
What does selective permeability mean in the context of biological
membranes?
Some substances can pass through the membrane while others cannot.
What is passive transport?
The movement of molecules across the membrane without the use of
energy, moving with their concentration gradient.
What is active transport?
The movement of molecules across the membrane against their
concentration gradient, using energy typically in the form of ATP.
What is a concentration gradient?
, The difference in concentration of a substance across a membrane.
What is osmosis?
The diffusion of water across a selectively permeable membrane.
What do isotonic, hypotonic, and hypertonic mean?
Isotonic: equal concentration; Hypotonic: lower concentration outside the
cell; Hypertonic: higher concentration outside the cell.
How do large molecules typically cross the plasma membrane?
Through vesicular transport mechanisms.
What is facilitated diffusion?
The process of transporting ions and large polar molecules across the
membrane via integral membrane proteins.
What is the role of channel proteins in facilitated diffusion?
They provide a central pore that allows specific ions or molecules to pass
through the membrane.
What is the membrane potential?
The charge imbalance across a membrane, typically measured at around -
70 mV in animal cells.
What factors affect diffusion rates across membranes?
Diameter of the transported molecules, temperature of the solution, and the
electrochemical gradient.
What is the difference between simple diffusion and facilitated diffusion?
Simple diffusion does not require proteins and occurs with small neutral
molecules, while facilitated diffusion requires membrane proteins for polar
and charged molecules.
What is the significance of the asymmetry of biological membranes?
Asymmetry affects the orientation of integral proteins and the distribution of
glycosylation on proteins.
