5 Written Questions
5 Matching Questions
- Receptor - mediated endocytosi
- Phospholipid bilayer
- Transport proteins
- Transport Across Cell Membranes: Concentration Gradient
- Membranes at Work 2. Kidney Dialysis
- 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 have 3-D shapes that make them highly selective, recognizing atoms or molecules by shape, size or charge.
- c receptors, like antennae, detect specific compounds or cells and bind with them, triggering endocytosis.
- d each phospholipid molecule has a head that is hydrophilic (water-loving) and two tails that are hydrophobic (water-fearing)
- e filters toxic wastes that accumulate in the blood while retaining necessary proteins, glucose, amino acids & ions
5 Multiple Choice Questions
- 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
- Peripheral proteins are partially embedded in the inside or outside surface of the membrane
- The cell wall of a plant resists the pressure of a water-filled vacuole keeping the plant firm
- when the lysosome bursts and releases it's digestive enzymes into the cell resulting in cell destruction
- a) phagocytosis - when cells "eat" by taking in large particles or other cells
b) pinocytosis - when cells "drink" by taking in droplets of fluid
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: A Biological Barrier → Cell membranes are semi-permeable allowing some materials to cross, while excluding others. They can select a) by particle size
- small enough to enter membrane - O2 H2O
- too large to cross - sugar
b) particular materials to transport across (they bind to chemicals based on their size shape or charge)
Three Types of Passive Transport → the diffusion of water molecules across a membrane (water molecules move from where they are more highly concentrated to where they are less concentrated)
Transport Across Cell Membranes: Equilibrium → a state at which molecules are evenly distributed (the concentration is equal throughout the medium)
- molecules continue moving but equilibrium is maintained
Bulk Transport → 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.