5 Written Questions
5 Matching Questions
- Hypotonic solution,
- Transport Across Cell Membranes: Concentration Gradient
- Three Types of Passive Transport 2.Osmosis
- Protein position within a membrane:
- Phospholipid bilayer
- a the difference in concentration between two areas for any given molecule produces a gradient or path of movement in which molecules move toward areas where the concentration of particles is lower
- molecules move down a concentration gradient
- b each phospholipid molecule has a head that is hydrophilic (water-loving) and two tails that are hydrophobic (water-fearing)
- c the diffusion of water molecules across a membrane (water molecules move from where they are more highly concentrated to where they are less concentrated)
- d Integral proteins extend through the entire bilayer and project from both surfaces
- e has a lower concentration of solute compared to inside the cell
5 Multiple Choice Questions
- the movement of molecules and ions against the concentration gradient which requires ATP energy and carrier proteins to pump these molecules from an area of low solute concentration to an area of high solute concentration.
- uses pressure to force contaminated water through a membrane with fine pores that will not allow bacteria, salts, and other dissolved molecules through, resulting in water with fewer impurities
- the movement of only certain substances across the cell membrane
- the use of vesicles to facilitate movement of substances that are too large to enter or exit the cell via transport proteins
- movement across cell membranes without an input of energy
2 reasons molecules move.
1. Brownian Motion
2. Concentration gradients
5 True/False Questions
Membranes at Work 3. Controlled Delivery of Medications → medication can be placed in a flat transdermal patch that sticks to the skin. A semi-permeable membrane lining the inner surface allows drugs to diffuse out of the patch at a slow, constant rate.
Cell Membrane Function: 6 materials a membrane prevents from entering the cell → - salts - atoms - viruses
- sugar - ions - bacteria
- proteins (7? this is what was in the notes)
most organelles are surrounded by membranes with the same structure as a cell membrane
Hypertonic solution → has a lower concentration of solute compared to inside the cell
Cell Membrane Function: A Biological Barrier → a cell membrane prevents many materials from entering the cell.
Two types of transport proteins → a) carrier proteins - facilitate the diffusion of glucose across the cell membrane
b) channel proteins - have tunnel-like pores filled with water that allow charged ions in and out of the cell