Chapter 3 Cells - 3-1Chapter 3Cell Structure and Function...

Info iconThis preview shows pages 1–18. Sign up to view the full content.

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

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

Unformatted text preview: 3-1Chapter 3Cell Structure and Function 3-2Cell Characteristics•Plasma Membrane–Outer cell boundary•Cytoplasm–Cytosol–Cytoskeleton–Cytoplasmic inclusions•Organelles–Specialized structures that perform specific functions3-3Functions of the Cell•Basic unit of life•Protection and support•Movement•Communication•Cell metabolism and energy release•Inheritance3-43-5Plasma Membrane•Flexible but sturdy barrier that surround cytoplasm of cell•Fluid mosaic model describes its structure–“sea of lipids in which proteins float like icebergs”–membrane is 50 % lipid & 50 % protein •held together by hydrogen bonds–lipid is barrier to entry or exit of polar substances–proteins are “gatekeepers” -- regulate traffic•50 lipid molecules for each protein molecule3-6Lipid Bilayer of the Cell Membrane•Phospholipids form a lipid bilayer–Hydrophilic(water-loving) polar heads–Hydrophobic(water-fearing) nonpolar heads•Cholesterol: Determines fluid nature of membrane3-7Membrane Proteins•Integral or intrinsic–Extend from one surface to the other•Peripheral or extrinsic–Attached to either the inner or outer surfaces of the lipid bilayer3-8Membrane ProteinsIntegral versus Peripheral Proteins3-9Marker Molecules•Allow cells to identify on another or other molecules•Glycoproteins•Glycolipids•Examples:–Immune system–Recognition of oocyte by sperm cell3-10Channel Proteins•Nongatedion channels–Always open•Ligand gatedion channel–Open in response to small molecules that bind to proteins or glycoproteins•Voltage-gatedion channel–Open when there is a change in charge across the plasma membrane3-11Receptors•Receptor molecules–Exposed receptor site•Linked to channel proteins–Acetylcholine•Linked to G proteins–Alter activity on inner surface of plasma membrane3-12Enzymes and Carrier Proteins3-13Movement through the Plasma Membrane•Diffusion•Osmosis•Filtration•Mediated transport mechanisms–Facilitated diffusion–Active transport–Secondary active transport3-14Diffusion•Movement of solutes from an area of higher concentration to lower concentration in solution–Concentration or density gradient•Difference between two points–Viscosity•How easily a liquid flows3-15Examples of Diffusion3-16Diffusion3-17Osmosis•Diffusionof water (solvent) across a selectively permeable membrane•Important...
View Full Document

{[ snackBarMessage ]}

Page1 / 65

Chapter 3 Cells - 3-1Chapter 3Cell Structure and Function...

This preview shows document pages 1 - 18. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online