Lecture10_103431 - Cell Signaling and Membrane Potential...

Info icon This preview shows pages 1–16. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style Cell Signaling and Membrane Potential October 14, 2010
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Cell Membrane Forms cell boundary Encloses intracellular contents Separates them from extracellular environment
Image of page 2
Cell Membrane Determines composition of cell Entry of nutrients Exit of wastes Exit of secretory products Maintain differences in ion concentrations Joins cells together Allows the cell to respond to environmental signals
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Extracellular and Intracellular Fluid Intracellular fluid Inside cells 2/3rds of total body H2O Extracellular fluid Outside of cells 1/3 of total body H2O 20% of ECF is blood plasma 80% of ECF is interstitial/tissue fluid Gel-like matrix
Image of page 4
Extracellular matrix Biological “glue” Intricate meshwork of fibrous proteins embedded in a watery, gel-like substance composed of complex carbohydrates Watery gel provides pathway for diffusion of nutrients, wastes, and other water-soluble traffic between the blood and tissue cells (interstitial fluid) Interwoven in this gel are three major types of protein
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Extracellular Matrix Protein fibers: collagen and elastin Gel-like ground subtance Interstitial fluid is part of the ground substance Contains glycoproteins = proteins with numerous sugar side chains Proteoglycans
Image of page 6
Extracellular matrix proteins Collagen : Forms cable-like fibers that assemble into sheets Provide tensile strength Elastin : Rubber-like fibers Most abundant in tissues that must be capable of stretching and recoiling (e.g. lungs) Fibronectin : Promotes cell adhesion and holds cells in position Levels are reduced in cancer
Image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Extracellular Matrix Collagen and elastin like iron bars in concrete— provide structural strength Collagen IV contributes to the basal lamina/basement membrane By forming chemical bonds between carbohydrates on the outside surface of the plasma membrane of overlying cells, glycoproteins and proteoglycans of the matrix strengthen the adhesions
Image of page 8
Plasma Membrane Composition Amphipathic phospholipids = Contain both polar (water- soluble/hydrophilic) and nonpolar (water- insoluble/hydrophobic) portions Self-assemble into bilayer Cholesterol = Give the membrane stability and fluidity Membrane proteins Integral and peripheral Carbohydrates
Image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Fluid Mosaic Model
Image of page 10
Membrane Proteins: Integral Proteins Channels Leak Gated Carriers
Image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Membrane Carbohydrates Self-recognition Cell-cell interactions Tissue growth
Image of page 12
Cell-Cell and Cell-Matrix Adhesions Cell adhesion molecules (CAMs) Specialized cell junctions Extracellular matrix “Glue” Fibrous proteins Collagen Elastin Fibronectin Carbohydrate gel
Image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Cell-Cell Adhesions Desmosomes Adhering Tight junctions Impermeable Gap junctions Communicating
Image of page 14
Desmosomes Act like “snaps” that anchor together two closely adjacent but non- touching cells Consists of two
Image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 16
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern