Download presentation
Presentation is loading. Please wait.
1
3.4 Diffusion and Osmosis 1. Cells are the basic unit of life
2
3.4 Diffusion and Osmosis Cells are the basic unit of life All living things are made of cells
3
3.4 Diffusion and Osmosis Cells must let nutrients in and waste out in order to survive
4
3.4 Diffusion and Osmosis Cell membrane made of phospholipid bilayer
5
3.4 Diffusion and Osmosis This makes cell membrane semipermeable (lets only some things in and out)
6
3.4 Diffusion and Osmosis semipermeable because membranes made of phospholipids with hydrophobic tail and hydrophilic head
7
3.4 Diffusion and Osmosis Passive transport does not require energy from a cell. Molecules can move across the cell membrane through passive transport. a. There are two types of passive transport. diffusion osmosis
8
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. 6. Diffusion - non-water molecules move from high concentration to low concentration Move from more crowded areas to less crowded areas
9
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. 7. Diffusion happens until concentrations reach equilibrium Equilibrium – when amounts of particles on inside and outside of cell are equal
10
3.4 Diffusion and Osmosis Facilitated Diffusion
Facilitated diffusion is passive transport when particles move in or out of the cell through special protein openings
11
3.4 Diffusion and Osmosis Some molecules can only diffuse through transport proteins. Some molecules cannot easily diffuse across the cell membrane. Facilitated diffusion is diffusion through transport proteins.
12
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. 8. Osmosis is the diffusion of water molecules across a semipermeable membrane.
13
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. REMEMBER: water always moves to where there is more stuff
14
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. There are three types of solutions. Hypotonic – more stuff inside the cell than outside Water moves into the cell isotonic hypertonic
15
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. There are three types of solutions. Hypotonic hypertonic – more stuff outside the cell than inside Water leaves the cell
16
3.4 Diffusion and Osmosis Diffusion and osmosis are types of passive transport. There are three types of solutions. Hypotonic Isotonic – same amount of stuff inside and outside cell Water moves in and out equally hypertonic
17
Active Transport Active Transport – when energy (ATP) is required for movement of particles Usually moves stuff from low concentration to high concentration Like rolling a ball up a hill
Similar presentations
