Biology

Chapter 7 Membrane Structure and Function Overview: Life at the Edge the plasma membrane is the boundary that separates the living cell from its nonliving surroundings selectively permeable: allows some substances to cross it more easily than others Concept 7.1: Cellular membranes are fluid mosaics of lipids and proteins a phospholipid is an amphipathic molecule, meaning it has both hydrophilic and hydrophobic regions head composed of phosphate group attached to one carbon of glycerol two fatty acid tails are hydrophobic in the fluid mosaic model, the membrane is a fluid structure with a ?mosaic? of various proteins embedded in or attached to a bilayer of phospholipids Membrane Models: Scientific Inquiry phospholipids are the most abundant lipid in the plasma membrane

Chapter 9: Cellular Respiration?Harvesting Chemical Energy Concept 9.6 (176 ? 178) is not required knowledge for the AP? exam and is omitted. Overview: Life Is Work living cells require transfusions of energy from outside sources to perform their tasks energy enters into an ecosystem as sunlight and leaves as heat Concept 9.1: Catabolic pathways yield energy by oxidizing organic fuels Catabolic Pathways and Production of ATP breakdown of organic molecules is exergonic fermentation is a partial degradation of sugars that occurs without oxygen cellular respiration is the most prevalent and efficient catabolic pathway consumes oxygen and organic molecules (i.e. glucose) yields ATP to keep working, cells must regenerate ATP Redox Reactions: Oxidation and Reduction

Chapter 11 Cell Communication Overview: The Cellular Internet essential for multicellular organism the combined effects of multiple signals determine cell response Concept 11.1: External signals are converted into responses within the cell Evolution of Cell Signaling yeast cells identify their mates by cell signaling a signal transduction pathway is a series of steps by which a signal on a cell?s surface is converted into a specific cellular response pathway similarities suggest that ancestral signaling molecules evolved in prokaryotes and were modified later in eukaryotes Local and Long Distance Signaling the concentration of signaling molecules allows bacteria to detect population density cells in a multicellular organism communicate via chemical messengers