Unit 1 - AOS 1 Flashcards
Hydrophobic
Water hating (eg. Tail of phospholipid).
Hydrophilic
Water loving (eg. Head of phospholipid).
Diffusion
The passive movement of particles from an area of high concentration to an area of low concentration, across a concentration gradient.
Osmosis
The passive movement of water molecules across a semi-permeable membrane (type of diffusion).
Isotonic
A solution where the concentration of water inside the cell is equal to the the concentration of water outside the cell (equilibrium).
Hypotonic
A solution where the concentration of water outside the cell is greater than the concentration of water inside the cell, therefore, the water moves into the cell.
Hypertonic
A solution where the concentration of water outside the cell is less than the concentration of water inside the cell, therefore, the water moves out of the cell.
Turgid
The swelling of a plant cell to account for the increase in water content.
Lyse
When a cell contains too much water, the cell membrane may rupture, which is known as lysing.
Flaccid
A cell which contains a low concentration of water, and deflates in size.
Plasmolysed
The contraction of the vacuole within a plant cell to account for a loss of water.
Facilitated diffusion
The movement of polar molecules (water-soluble) in/out of the cell via transport proteins across the cell membrane (does not require energy).
Passive transport
The transport of molecules across the plasma membrane, moving down the concentration gradient (does not require energy).
Active transport
The transport of molecules in/out of the cell, moving against the concentration gradient, moving from low to high concentration (requires energy).
Exocytosis
The transport of large molecules out of the cell. The molecules are packaged into a vesicle and moved against the concentration gradient (requires energy).
