Transcript cell wall
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: 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 Which way will molecules move? What process is it? 10% Water 100% Water Time Osmosis High sugar Low Sugar Time Diffusion Osmosis can effect plant and animal cells differently Can you think of which cell organelle that a plant has which an animal cell does not, that may have something to do with this? The Cell Wall!! Plant Cells 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: Plant Cells HYPO = less TONIC = solution HYPOTONIC CELL 100% H2O HYPER= more TONIC = solution HYPERTONIC CELL 90% H2O 10% NaCl 97% H2O Water rushes into cell, keeps cell rigid 97% H2O Water moves out of cell, Cell membrane pulls away from cell wall PLASMOLYSIS HYPOTONIC CELL 100% H2O 90% H2O - Water rushes into cell - Cell swells and may burst due to lack of cell wall HYPERTONIC CELL 95% H2O 100% H2O - Water rushes out of cell - Cell shrinks due to lack of cell wall ISOTONIC CELL 97% H2O 97% H2O - Cell does not change, water equal inside and out Equilibrium/Homeostasis ISO = same TONIC = solution 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 What do you know? What are the 2 general types of cell transport and what is the difference between them? How does a selectively permeable membrane work? What is diffusion? What is osmosis and how is it different in plant and animal cells? What is the difference between hypertonic, hypotonic, and isotonic cells? What are the 2 types of active transport and how do they work?