Diffusion Movement of molecules from an area where there are many to an area where there are few
Movement of Materials in a Cell
Selectively Permeable Membrane- [like a strainer] - contains different size openings called pores - only materials smaller than openings pass through
Diffusion- Movement of molecules from an area where there are many to an area where there are few Examples: food coloring in water, spraying air freshener Simple Rule: HIGH TO LOW IS THE FLOW CONTINUES UNTIL ……. Equilibrium/Homeostasis- molecules are equally distributed in an area
Osmosis- movement of WATER molecules from an area where there are many to an area where there are few
Plasmolysis- cell membrane shrinking away from Fresh Water Salt Water Cell Membrane Plasmolysis- cell membrane shrinking away from cell wall, due to water exiting cell Why? Salt is a substance that will draw water in its direction. This is why you feel thirsty when you eat something salty. Simple Rule: Salt Sucks
Plant Cells HYPOTONIC CELL HYPERTONIC CELL 10% NaCl PLASMOLYSIS HYPER= more TONIC = solution HYPO = less TONIC = solution HYPOTONIC CELL HYPERTONIC CELL 100% H2O 90% H2O 10% NaCl 97% H2O 97% H2O Water rushes into cell, keeps cell rigid Water moves out of cell, Cell membrane pulls away from cell wall PLASMOLYSIS
Animal Cells HYPOTONIC CELL HYPERTONIC CELL 95% H2O 100% H2O 90% H2O - Water rushes into cell - Cell swells and may burst due to lack of cell wall - Water rushes out of cell Cell shrinks due to lack of cell wall
ISO = same TONIC = solution ISOTONIC CELL 97% H2O 97% H2O Cell does not change, water equal inside and out Equilibrium/Homeostasis
Animal cells and water movement
Why do fingers and toes wrinkle?
Active Transport - requires energy Endocytosis- process used by cells to transport large materials [proteins] INTO cell Greek terms : ENDO = inside CYTOSIS = relates to cell
Exocytosis- process used by cell to move wastes or other materials OUT of cell Greek terms : EXO = outside CYTOSIS = relates to cell