1.3: Cell membranes and transport

What the cell membrane is made of

Sheets of phospholipids facing each other

Can be embedded in either surface of the phospholipid bilayer, provides structural support, forms recognition sites, identifying cells and receptor sites for hormone attachment

Extend across both layers of the phospholipid bilayer, includes transport proteins

Allow molecules or ions to pass through during active or passive transport

Structural model of the plasma membrane where molecules are free to move sideways within a lipid bilayer

A protein with one or more covalently attached carbohydrates

Membrane carbohydrates that are covalently bonded to lipids

A carbohydrate coat covering the cell surface, has roles in cell-to-cell recognition and adhesion, and hormone receptors

Passive transport - ions and molecules move from an area of high concentration and low concentration

Allows water-soluble molecules through the membrane via transport proteins

Transport protein that works by molecules binding to the protein, which reshapes to allow them through

Transport protein that works by operating by a gate like process, opening and closing when molecules are necessary

Diffusion that happens against a concentration gradient - requires ATP

Water diffusion, where an area with a high water potential will move down a concentration gradient to an area with low water potential

The measure of free water molecules and the tendency of water to move

How easily water molecules moves out of a solution

What water, pressure and solute potential are measured by

The pull of a solution with a low water potential on water molecules

The pressure exerted by the cell wall on the cell contents.

When a plant cell can take in no more water, supports the plant structure

A solution with a higher water potential than the cell it surrounds

A solution with a lower water potential than the cell it surrounds

The start of plasmolysis - when the cytoplasm begins to move away from the cell wall

A process where the vacuole shrinks, causing the cytoplasm to move away from the cell wall

When the solution has the same water potential as the cell it surrounds

When an animal cell bursts due to being surrounded by a hypotonic solution

What an animal cell becomes if it is placed in a hypertonic solution

When materials are absorbed by extensions of the cell membrane and cytoplasm and coverted to vesicles, requires ATP

A form of endocytosis, occurs when solid material is too large to be taken up by other methods

A form of endocytosis, when liquids are unable to be taken up by other methods

How substances leave the cell - turning to vesicles and fusing with the cell membrane

Inhibit the production of ATP, therefore limiting active transport