Module 4.1 - Passive Transport

Phospholipid

The cell membrane is a blank bilayer.

Cell Membrane

Controls what comes in and out of the cell to maintain internal balance.

Selective Permeability

Defined as controlling what comes in and out of something.

Homeostasis

Internal balance inside the body.

Phospholipids

These are the main component in cell membranes.

Phospholipids

They line up in a bilayer arrangement, acting as a barrier to water soluble molecules.

Head and fatty acid tails

Structure of Phospholipids.

Polar

The head of the phospholipid structure is blank.

Hydrophilic

The head of the phospholipid is blank (water loving).

Soluble

The head of the phospholipid is blank in water.

Non-polar and hydrophobic

The fatty acid tails are blank and blank (water hating).

Insoluble

The fatty acid tails are blank in water.

Amphiphatic

Phospholipids are blank as they have both hydrophilic and hydrophobic parts.

Transmembrane Proteins

Integral membrane proteins.

Transport, receptor, adhesion

Functions of transmembrane proteins.

Interior protein network

Peripheral or intracellular membrane proteins.

Cell signaling, structural support

Functions of interior protein network

Cell surface markers

Glycoproteins and glycolipids

Identification and communication

Functions of cell surface markers

Transmembrane proteins, interior protein network, cell surface markers

Structure of the cell membrane

Transport

Controlled movement of molecules from one side of a membrane to the other.

Membrane proteins

Transport through the cell membrane is accomplished by blank.

Specific

Transport through the membrane is blank (only allows certain molecules).

High to low

Concentration gradient in passive transport is from blank to blank concentration.

Diffusion, facilitated diffusion, osmosis

Types of passive transport

Protein pumps, endocytosis, exocytosis

Types of active transport

Active transport

Requires energy from the cells.

Diffusion

Random movement of particles from an area of high to low concentration.

Diffusion

Continues until all molecules are evenly spaced (equilibrium).

Diffusion

Molecules continue to move but stay spread out.

Simple Diffusion

Particles move from high to low concentration—that is, they move down their concetration gradient.

Osmosis

Diffusion of water through a selectively permeable membrane.

Hypotonic Solution

The solution has a lower concentration of solutes and higher concentration of water than inside the cell.

Hypotonic Solution

Low solute, high water

Cytolysis

Cell swelles until it bursts open.

Hypertonic Solution

The solution has a higher concentration of solutes and lower concentration of water than inside the cell (high solute, low water)

Plasmolysis

Cell shrino/shrivels as water moves from cell to solution.

Isotonic Solution

The solution has an equal concentration of solutes inside the cell.

Equilibrium

Cell functions as normal.

Cell walls, over-expanding

Bacteria and Plants have blank to prevent from blank.

Isotonic, removing excess salt

Kidneys in our body filter our blood and keep it blank by blank.

Facilitated Diffusion

Diffusion of specific particles through the transport proteins found in the membrane.

Transport Proteins

Specific; they select only certain molecules.

Proteins, larger or charged molecules

Facilitated Diffusion transfers:

Hydrophobic, hydrophilic

The blank tails of phospholipids repel blank substances.

ions, polar substances, protein channel

Blank and blank must pass through a blank to cross the membrane.