Transport Across Membranes Flashcards
The Cell Membrane has Proteins which form Channels that allow Substances to enter and leave the cell.
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What is the Cell Membrane made up of?
Phospholipids and Proteins.
Passive transport is DOWN a concentration gradient and does not require energy.
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Diffusion is an example of Passive Transport, what is diffusion?
Diffusion is the movement of a substance from an area of high concentration to an area of low concentration until the concentration is equal.
What are examples of substances that diffuse across the membrane?
Glucose, Carbon Dioxide, Oxygen and Amino Acids.
What is Osmosis?
Osmosis is the movement of Water Molecules from an area of high water concentration to an area of low water concentration through a selectively permeable membrane.
Water moving into an animal cell can cause it to burst, what can happen if water moves out?
It can shrink.
Water moving into a plant cell can cause it to be Turgid, what can happen if water moves out of a plant cell?
It can become Plasmolysed.
What is active Transport?
It is the movement of a substance from an area of low concentration to high concentration, against a concentration. The process requires energy.
What are examples of substances actively transported across membranes?
Sodium and potassium.
What is an example of a substance actively transported across the cell membrane is sea weed?
Iodine.
