Types of Transport
What is Passive Transport?
Passive transport is the movement of molecules across the cell membrane without the use of energy.
What is the primary function of the cell membrane?
The primary function of the cell membrane is to control what enters and leaves the cell.
Osmosis is the diffusion of water molecules across a semipermeable membrane.
What occurs to a cell in a hypertonic solution?
In a hypertonic solution, the cell will lose water and shrink.
What are channel proteins?
Channel proteins are proteins that provide tunnel-like pathways for specific molecules to cross the cell membrane.
What is active transport?
Active transport is the movement of molecules against their concentration gradient, requiring ATP energy.
How do proteins function in the cell membrane?
Proteins facilitate transport, act as receptors, and provide structural support.
What is Endocytosis?
Endocytosis is the process by which a cell takes in large particles by engulfing them with the cell membrane.
What occurs to a cell in a hypotonic solution?
In a hypotonic solution, water will move into the cell, causing it to swell and possibly burst.
What is the function of carrier proteins?
Carrier proteins enclose specific molecules, and change shape to transport them across the membrane.
What is the name one type of passive transport?
One type of passive transport is diffusion, osmosis, or facilitated diffusion.
What role do proteins play in the cell membrane?
Proteins in the cell membrane help transport substances, act as receptors, and provide structural support.
What is Exocytosis?
Exocytosis is the process by which a cell releases large particles outside by packaging them in vesicles, made from the cell membrane, and releasing them outside of the cell.
What happens to a cell in an isotonic solution?
In an isotonic solution, the cell remains the same as the concentration of solutes is equal inside and outside the cell.
How do aquaporins function in cells?
Aquaporins are specialized channel proteins that facilitate the rapid movement of water molecules across the cell membrane
What is the difference between facilitated diffusion and simple diffusion?
Facilitated diffusion involves the use of transport proteins to help molecules cross the membrane, while simple diffusion does not.
What does it mean for a membrane to be selectively permeable?
A selectively permeable membrane allows certain substances to pass through, while blocking others.
What is the sodium-potassium pump?
The sodium-potassium pump is a type of active transport that moves sodium ions out of the cell and potassium ions into the cell, using ATP.
What is equilibrium, in terms of concentration when thinking about diffusion?
Equilibrium in terms of concentration means that the concentrations of substances are equal on both sides of the membrane.
What is the primary function of channel proteins?
The primary function of channel proteins is to provide a pathway for specific molecules or ions to cross the cell membrane.
Name a characteristic of passive transport.
It allows molecules to move on the concentration gradient without the use of energy.
How do lipids contribute to membrane structure?
Lipids form the phospholipid bilayer, which provides the basic structure of the membrane and contributes to its fluidity.
Why do cells need to use energy during active transport?
Cells need to use energy during active transport to move substances against their concentration gradient.
In regard to diffusion, why do cells need to maintain a water balance (osmotic balance)?
Cells need to maintain a water balance (osmotic balance) to prevent excessive swelling or shrinking, which can disrupt cellular functions.
Gated channel proteins have the same tunnel-like structure as a channel protein, while also having a flap on the inside and outside of the cell that opens and closes allowing molecules to flow into the cell.