Campbell Biology 9th Edition Chapter 7 Summary Roll
Campbell Biology Chapter 7 study guide by shoda2016 includes 27 questions covering vocabulary, terms and more. Quizlet flashcards, activities and games help you improve your grades.
No notes for slide. For the Cell Biology Video Structure of the Cell Membrane, go to Animation and Video Files.
Figure 7.2 Phospholipid bilayer (cross section). Figure 7.3 The original fluid mosaic model for membranes. Figure 7.5 Updated model of an animal cell ’s plasma membrane (cutaway view). Figure 7.6 The movement of phospholipids. Figure 7.8 Factors that affect membrane fluidity.
Figure 7.9 The structure of a transmembrane protein. Figure 7.10 Some functions of membrane proteins. Figure 7.11 IMPACT: Blocking HIV Entry into Cells as a Treatment for HIV Infections. Figure 7.12 Synthesis of membrane components and their orientation in the membrane. Figure 7.13 The diffusion of solutes across a synthetic membrane. Figure 7.14 Osmosis. Figure 7.15 The water balance of living cells.
Figure 7.16 The contractile vacuole of Paramecium caudatum. For the Cell Biology Video Water Movement through an Aquaporin, go to Animation and Video Files. Figure 7.17 Two types of transport proteins that carry out facilitated diffusion.
For the Cell Biology Video Na + /K + ATPase Cycle, go to Animation and Video Files. Figure 7.19 Review: passive and active transport.
Figure 7.20 A proton pump. Figure 7.21 Cotransport: active transport driven by a concentration gradient. For the Cell Biology Video Phagocytosis in Action, go to Animation and Video Files.
Figure 7.22 Exploring: Endocytosis in Animal Cells. Figure 7.22 Exploring: Endocytosis in Animal Cells. Figure 7.22 Exploring: Endocytosis in Animal Cells. 07 membrane structure and function.
1. LECTURE PRESENTATIONS For CAMPBELL BIOLOGY, NINTH EDITION Jane B.
Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B.
JacksonChapter 7Membrane Structure andFunction Lectures by Erin Barley Kathleen Fitzpatrick© 2011 Pearson Education, Inc. Overview: Life at the Edge. The plasma membrane is the boundary that separates the living cell from its surroundings. The plasma membrane exhibits selective permeability, allowing some substances to cross it more easily than others© 2011 Pearson Education, Inc. Cellular membranes are fluid mosaics oflipids and proteins.
Phospholipids are the most abundant lipid in the plasma membrane. Phospholipids are amphipathic molecules, containing hydrophobic and hydrophilic regions. The fluid mosaic model states that a membrane is a fluid structure with a “mosaic” of various proteins embedded in it© 2011 Pearson Education, Inc. Membrane Models: Scientific Inquiry. Membranes have been chemically analyzed and found to be made of proteins and lipids. Scientists studying the plasma membrane reasoned that it must be a phospholipid bilayer© 2011 Pearson Education, Inc.
Figure 7.2 WATER Hydrophilic head Hydrophobic tail WATER. In 1935, Hugh Davson and James Danielli proposed a sandwich model in which the phospholipid bilayer lies between two layers of globular proteins. Later studies found problems with this model, particularly the placement of membrane proteins, which have hydrophilic and hydrophobic regions. In 1972, S. Singer and G. Nicolson proposed that the membrane is a mosaic of proteins dispersed within the bilayer, with only the hydrophilic regions exposed to water© 2011 Pearson Education, Inc.
Figure 7.3 Phospholipid bilayer Hydrophobic regions Hydrophilic of protein regions of protein. The Fluidity of Membranes. Phospholipids in the plasma membrane can move within the bilayer. Most of the lipids, and some proteins, drift laterally. Rarely does a molecule flip-flop transversely across the membrane© 2011 Pearson Education, Inc.
Figure 7.5 Fibers of extra- cellular matrix (ECM) Glyco- Carbohydrate protein Glycolipid EXTRACELLULAR SIDE OF MEMBRANE Cholesterol Microfilaments Peripheral of cytoskeleton proteins Integral protein CYTOPLASMIC SIDE OF MEMBRANE. Figure 7.6 Lateral movement occurs Flip-flopping across the membrane ∼107 times per second. Is rare (∼ once per month).
As temperatures cool, membranes switch from a fluid state to a solid state. The temperature at which a membrane solidifies depends on the types of lipids. Membranes rich in unsaturated fatty acids are more fluid than those rich in saturated fatty acids. Membranes must be fluid to work properly; they are usually about as fluid as salad oil© 2011 Pearson Education, Inc. The steroid cholesterol has different effects on membrane fluidity at different temperatures.
At warm temperatures (such as 37°C), cholesterol restrains movement of phospholipids. At cool temperatures, it maintains fluidity by preventing tight packing© 2011 Pearson Education, Inc. Figure 7.8 Fluid Viscous Unsaturated hydrocarbon Saturated hydrocarbon tails tails (a) Unsaturated versus saturated hydrocarbon tails (b) Cholesterol within the animal cell membrane Cholesterol. Membrane Proteins and Their Functions.
A membrane is a collage of different proteins, often grouped together, embedded in the fluid matrix of the lipid bilayer. Proteins determine most of the membrane’s specific functions© 2011 Pearson Education, Inc. Peripheral proteins are bound to the surface of the membrane. Integral proteins penetrate the hydrophobic core. Integral proteins that span the membrane are called transmembrane proteins.
Campbell Biology 9th Edition Chapter 7 Summary Roll Free
The hydrophobic regions of an integral protein consist of one or more stretches of nonpolar amino acids, often coiled into alpha helices© 2011 Pearson Education, Inc. Figure 7.9 EXTRACELLULAR SIDE N-terminus α helix C-terminus CYTOPLASMIC SIDE. Six major functions of membrane proteins – Transport – Enzymatic activity – Signal transduction – Cell-cell recognition – Intercellular joining – Attachment to the cytoskeleton and extracellular matrix (ECM)© 2011 Pearson Education, Inc.