1. Chapter 7: Cells

2.  1) Regulates what goes in and out  (selectively permeable- some molecules too large or too strongly charged to cross while others can pass through easily)  2) Protects & supports cell

3.  Made up of: phospholipids, carbohydrates, and proteins  Phospholipids-  1) hydrophilic heads- “water loving”, attracted to water  2) hydrophobic tails- “water hating”, fatty acid ends, repelled

5.  STOP: COMPLETE INQUIRY ACTIVITY

7.  When mixed with water  tails cluster together and heads attracted toward water; heads exposed to outside and inside of cell, while tails form oily layer inside membrane that keeps water out  Phospholipid bilayer- double-layered sheet of phospholipids, “fluid mosaic model”

8.  Fluid Mosaic Model Video Fluid Mosaic Model Video  Proteins  integral and peripheral  Integral- embedded within layer; form channels and pumps that help move substances across membrane  Peripheral- temporarily attaches to the biological membrane, either to the lipid bilayer or to integral proteins; cell signaling  Carbohydrates- many attached to proteins allowing individual cells to identify each other

9.  Enzymatic  Receptors  Transport materials  Communications  Adhesion