Human development

Chapter 4: Carbon and the Molecular Diversity of Life 4 Major Macromolecules: Lipids Carbohydrates Nucleic Acid Protein Lipids Fat- a combination of a glycerol and three fatty acids also called a triglyceride Used for long term energy storage, which is located in the long carbon chains Phospholipid- a combination of a glycerol, two fatty acids and a phosphate group Makes up cell membrane (lipid bilayer) Selectively permeable Hydrophilic heads (the phosphate group) Hydrophobic tails Steroid- lipids with a structure of four fused rings General Information Glycerol is combined to fatty acid by an ester linkage (dehydration synthesis) Ester linkage is polar CH2 groups are nonpolar Saturated Fat- a triglyceride with only single bonds

Chapter 5: Membrane Transport and Cell Signaling Amphiphatic- refers to something that has both hydrophilic and hydrophobic regions the cell membrane proteins Fluidity Low Temperatures-less fluid because the phospholipids pack together tightly Factors that Affect Fluidity: Amount of phospholipids- phospholipids have kinks in the tails due to their hydrogen bonds which make them harder to pack Cholesterol- inhibits the packing of the phospholipid tails at LOW TEMPERATURE. AT HIGH TEMPERATURE, it solidifies the membrane because it inhibits the movement of tails Proteins in the Membrane Intergal-penetrate the membrane, hydrophobic exterior, hydrophilic interior Peripheral-lie on either side of the membrane Major Protein Functions: -Transport-allows materials to diffuse