University of Santo Tomas
Faculty of Pharmacy, BS Pharmacy Batch 2027
PHA611: Pharmaceutical Botany with Taxonomy (Laboratory)
Exercise 4: Cellular Transport • measure of relative tendency of water to move from one
area to another caused by osmosis
Cellular Transport: how molecules move inside the cell;
• Affected by the presence of solute in solution
exchange of materials; involves movement of solute between
cells and its environment
Tonicity
• Ability of an extracellular solution to make water move
Water: most abundant inorganic molecule (60–70% cell volume,
into or out of a cell by osmosis
90% if cell is turgid)
Isotonic
TYPES OF CELLULAR TRANSPORT • Equal solute concentration
• E.g. normal saline solution (NSS): 0.89% or 0.9%
Diffusion
NaCl solution
• Passive transport
• Movement of particles because of their kinetic energy Hypertonic
following concentration gradient • Greater solute concentration than the cell
• Concentration gradient: higher to lower concentration • More dissolved solute = lower water potential
area • Water moves out of the cell
• E.g. CO2 diffusion from atmosphere to leaves, O 2 • > 0.89% NaCl
diffusion from plant to environment
Hypotonic
Factors affecting diffusion • Lower solute concentration than the cell
• Temperature (directly proportional) • less dissolved solute = higher water potential
• Nature of cytoplasm (inversely proportional: the more • water moves inside the cell
viscous, the slower the diffusion rate)
• < 0.89% NaCl
• Pressure (directly proportional) • E.g. distilled water
• Size of molecules
Cell Conditions
Imbibition
• Flaccid/normal: equal solute concentration inside and
• Passive transport outside of the cell
• Absorption (penetration) and adsorption (adheres to • Plasmolyzed: shrunk cell due to water loss
surface) of water by insoluble, colloidal, and o Plasmolysis: process of cell wall shrinking away
hydrophilic material (cell wall) from cytoplasm
• Polar molecules attract and dissolve polar molecules o Protoplasm shrinks and detaches from cell wall due
o E.g. water, sucrose, ethanol, ammonia, sulfur to water loss
dioxide, hydrogen sulfide o Low water concentration outside the cell
o High salt or sugar concentration outside the cell
Osmosis • Turgid: swelled, enlarged cell due to water uptake
• Movement of water across a semipermeable o High water concentration outside the cell
membrane between 2 solutions o Turbo pressure: cell wall exerts pressure against
• Moves from higher to lower concentrated areas cell membrane
• Only living/biological systems have permeable o Cytolysis: process of cell bursting due to excessive
membranes influx of water
Water potential
1|P a g e
LIANRPh
Faculty of Pharmacy, BS Pharmacy Batch 2027
PHA611: Pharmaceutical Botany with Taxonomy (Laboratory)
Exercise 4: Cellular Transport • measure of relative tendency of water to move from one
area to another caused by osmosis
Cellular Transport: how molecules move inside the cell;
• Affected by the presence of solute in solution
exchange of materials; involves movement of solute between
cells and its environment
Tonicity
• Ability of an extracellular solution to make water move
Water: most abundant inorganic molecule (60–70% cell volume,
into or out of a cell by osmosis
90% if cell is turgid)
Isotonic
TYPES OF CELLULAR TRANSPORT • Equal solute concentration
• E.g. normal saline solution (NSS): 0.89% or 0.9%
Diffusion
NaCl solution
• Passive transport
• Movement of particles because of their kinetic energy Hypertonic
following concentration gradient • Greater solute concentration than the cell
• Concentration gradient: higher to lower concentration • More dissolved solute = lower water potential
area • Water moves out of the cell
• E.g. CO2 diffusion from atmosphere to leaves, O 2 • > 0.89% NaCl
diffusion from plant to environment
Hypotonic
Factors affecting diffusion • Lower solute concentration than the cell
• Temperature (directly proportional) • less dissolved solute = higher water potential
• Nature of cytoplasm (inversely proportional: the more • water moves inside the cell
viscous, the slower the diffusion rate)
• < 0.89% NaCl
• Pressure (directly proportional) • E.g. distilled water
• Size of molecules
Cell Conditions
Imbibition
• Flaccid/normal: equal solute concentration inside and
• Passive transport outside of the cell
• Absorption (penetration) and adsorption (adheres to • Plasmolyzed: shrunk cell due to water loss
surface) of water by insoluble, colloidal, and o Plasmolysis: process of cell wall shrinking away
hydrophilic material (cell wall) from cytoplasm
• Polar molecules attract and dissolve polar molecules o Protoplasm shrinks and detaches from cell wall due
o E.g. water, sucrose, ethanol, ammonia, sulfur to water loss
dioxide, hydrogen sulfide o Low water concentration outside the cell
o High salt or sugar concentration outside the cell
Osmosis • Turgid: swelled, enlarged cell due to water uptake
• Movement of water across a semipermeable o High water concentration outside the cell
membrane between 2 solutions o Turbo pressure: cell wall exerts pressure against
• Moves from higher to lower concentrated areas cell membrane
• Only living/biological systems have permeable o Cytolysis: process of cell bursting due to excessive
membranes influx of water
Water potential
1|P a g e
LIANRPh
