Unit 1 1.2 Transport Across Membrane Flashcards
All living things have a
Membrane
The membrane has constantly mobile phospholipid (fat) molecules with proteins embedded in a??
Mosaic pattern.
The cell membrane contains?
Phospholipid molecules, arranged in a double layer. This layer is constantly moving, allowing the cell to change shape.
A patchy mosaic of protein molecules is??
Pores in the proteins form channels
The membrane is made of??
protein and phospholipids.
If protein or phospholipids become damaged, the so does the
Membrane
Proteins become damaged at???
high temperatures.
Phospholipids are soluble in
Alcohol
The membrane contains proteins that have channels, which allows
molecules to move into and out of the cell.
Small molecules can pass through slowly, larger molecules must ….
First be broken down.
A concentration gradient is the difference in
concentration between two solutions.
Passive transport is the movement of a substance _________ a concentration gradient.
Passive transport is the movement of a substance Passive transport is the movement of a substance DOWN a concentration gradient. a concentration gradient.
This does not require ____________.
This does not require ENERGY
Diffusion is the name given to the movement of molecules of a
substance
Diffusion is the movement of molecules ___________ a concentration gradient from a __________concentration to a __________ concentration
Diffusion is the movement of molecules DOWN a concentration gradient from a HIGHER concentration to a LOWER concentration
Molecules that move by diffusion do not require ________________ to move. For this reason diffusion is an example of ________________ transport
Molecules that move by diffusion do not require ENERGY to move. For this reason diffusion is an example of PASSIVE transport
Diffusion is used by
cells to move useful substances into cells and waste products out.
Osmosis is the special name given to the diffusion of water. Like diffusion, osmosis is also a passive process, so does not
require energy.
Cells can gain or lose water by ______________, depending on the ______________ concentration of the solution inside the cell compared to water concentration of the solution _______________ the cell.
Cells can gain or lose water by OSMOSIS, depending on the WATER concentration of the solution inside the cell compared to water concentration of the solution OUTSIDE the cell.
Osmosis is the movement of water molecules from a _____________ water concentration to a _____________ water concentration through a __________ permeable membrane
Osmosis is the movement of water molecules from a HIGHER water concentration to a LOWER water concentration through a SELECTIVELY permeable membrane
When a plant cell is placed in pure water it swells up due to water diffusing in and filling the vacuole, the word to describe this is?.
TURGID
When a plant cell is left in a strong sugar solution the water diffuses out, causing the cell contents to shrink away from the cell wall. This cell is now described as being
Plasmolysed
Active transport is the movement of molecules or ions from a region of ___________ concentration to a region of higher concentration _____________ a concentration gradient
Active transport is the movement of molecules or ions from a region of LOWER concentration to a region of higher concentration AGAINST a concentration gradient
As this process works against the concentration gradient it requires _______________. Membrane proteins use this energy to move the molecules or ions.
As this process works against the concentration gradient it requires ENERGY Membrane proteins use this energy to move the molecules or ions.
An example of active transport in the human body occurs in???
nerve cells
