Write Cell Transport

Molecules can pass through the cell membrane in four ways Write Molecules can pass through the cell membrane in four ways Directly through the membrane (phospholipid bilayer) Membrane Channels Carrier Molecules Vesicles

Cell transport can be categorized into two major groups Write Cell transport can be categorized into two major groups Passive Transport NO ENERGY NEEDED Goes with concentration gradient Active Transport ENERGY NEEDED Goes with concentration gradient Diffusion Facilitated Diffusion Osmosis Filtration Endocytosis Pinocytosis Phagocytosis Receptor-mediated endocytosis Exocytosis

Write Cell Transport Movement of things in and out of the cell occurs between two solutions. Extracellular Fluid = Solution outside of the cell Intercellular Fluid = Solution inside of the cell Intracellular Fluid Intracellular Fluid Intracellular Fluid Intracellular Fluid Intracellular Fluid Cell Cell Cell Cell Cell Extracellular Fluid

Write Diffusion The movement of particles (solutes) from an area of high concentration to low concentration until equilibrium is met.

Diffusion Intracellular Fluid (Cytoplasm) Extracellular Fluid Hypertonic Isotonic Intracellular Fluid (Cytoplasm) Hypotonic Isotonic

Body Example: Breathing Listen Body Example: Breathing

Diffusion = Solute moves from HYPERTONIC  HYPOTONIC Write Diffusion Diffusion always moves from Hypertonic (high solutes) to hypotonic (low solutes) solutions. Diffusion = Solute moves from HYPERTONIC  HYPOTONIC

Facilitated Diffusion Faciliated Diffusion Diffusion with the aid of a carrier protein or protein channel Used for larger molecules such as sugars and amino acids carrier protein or protein channel is specific to one molecule

Write Osmosis The movement of water (solvent) between two solutions until equilibrium is met. Occurs when solutes cannot pass through the cell membrane.

Osmosis = Water moves from HYPOTONIC  HYPERTONIC Write Osmosis Osmosis always moves from hypotonic solutions (low solutes, but high solvent) to hypertonic solutions (high solutes, but low water) Osmosis = Water moves from HYPOTONIC  HYPERTONIC

Osmosis and Animal Cells Listen Osmosis and Animal Cells Hypertonic Extracellular Fluid Isotonic Extracellular Fluid Hypotonic Extracellular Fluid No water movement. Cell stays the same. Water moves out of the cell. Cell Shrinks. Water moves into the cell. Cell expands. Water is moving from the HYPOTONIC cell to the HYPERTONIC solution Water is moving from the HYPOTONIC solution to the HYPERTONIC CELL

Write Filtration Passage of materials through the membrane due to pressure from the cardiovascular system

Listen

Endocytosis Movement of particles into the cell via vesicles Write Endocytosis Movement of particles into the cell via vesicles Requires energy Pinocytosis “Cell drinking” Cell takes in extracellular fluid with some small particles Phagocytosis Cell Eating Cell takes in large particles in the extracellular fluid White blood cells eat a lot of bacteria this way Receptor mediated Endocytosis Receptors must be activated before endocytosis can occur

Exocytosis Movement of particles out of the cell via vesicles Write Exocytosis Movement of particles out of the cell via vesicles Requires energy