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Listing 1 - 10 from 16 for cell membrane

Structure and Function of Organelles
... advantage of the compartmentalization of the eukaryotic cell: the cell could not support such destructive enzymes if they were not contained in a membrane-bound lysosome . There is a very nice ... are still extremely important components of the cellular system. They are the cell membrane, the cytoplasm, and the cytoskeleton. The cell membrane is so important that we devote the entire next module to ...
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ESG 7.01 Knowledge Noodle Main Page
... . Central Metabolic Biochemistry What are the functions of a cell membrane, anyway? How do the organelles work that provide energy for the cell? What are the chemical reactions that convert energy ... communicate with one another? How do groups of cells coordinate their activities? Readings: Hypertext Cell Biology Purves, Chapter 12 and 13: Gene Expression in Eukaryotes;Chapter 4: Organization of ...
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1.1 Membrane Structure and Composition
... makes the membrane more fluid. Therefore, one way for a cell to control the fluidity of its membrane is by regulating its level of cholesterol in the cell membrane. Another way for the cell to control the fluidity of its membrane is to ...
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Membrane Transport Mechanisms
... Facilitated diffusion utilizes membrane protein channels to allow charged molecules (which otherwise could not diffuse across the cell membrane) to freely diffuse in a nd out of the cell. These channels comes ... into the cell and Na+ out of the cell at the same time, with the expenditure of ATP. Secondary active transport involves using energy to establish a gradient across the cell membrane, and ...
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Cell Biology Problems
... path of acetylcholine within the cell, and see that it is first synthesized, then chemically modified, stored for a while, and eventually transported to the plasma membrane. a) Describe the path ... esgfun throughout the membrane? Neurons and other excitable cells have membranes that are polarized: there is a voltage difference across the plasma membrane such that the inside of the cell is negative ...
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The Lac Operon
... by the gene LacZ. Lactose Permease: This enzyme spans the cell membrane and brings lactose into the cell from the outside environment. The membrane is otherwise essentially impermeable to lactose. It is coded for ... for transcription upon the addition of lactose. When levels of glucose (a catabolite) in the cell are high, a molecule called cyclic AMP is inhibited from forming. So when glucose levels ...
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Other Regulated Systems
... free for RNA polymerase and transcription proceeds, making tryptophan biosynthetic genes and replenishing the cell's supply of tryptophan. This kind of feedback inhibition of transcription is very common ... unique small molecule called VAI (Vibrio fischeri autoinducer) that can diffuse readily through the cell membrane. Thus, there is a declining concentration of the small molecule in a growing ...
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Cell Biology Chapter
... membrane-spanning proteins Receptors Growth Factor Receptors Transmembrane signal transduction G Protein Receptors epinephrine Cytoplasmic signal transduction Signalling cascades Membrane transport mechanisms Diffusion Facilitated diffusion Active transport The Glucose-Na+ Transport System Cell ...
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Membrane Proteins
... Membrane Proteins Membrane Proteins Transmembrane Proteins Membrane proteins are either extrinsic or intrinsic. Extrinsic membrane proteins are entirely outside of the membrane, but are bound to it by weak molecular ... protrude into the extracellular membrane. A typical mammalian cell may have several hundred distinct types of glycoprotein studding its plasma membrane. Each of these glycoproteins ...
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Membrane Proteins Introduction
... Membrane Proteins Introduction Membrane Proteins Introduction Membranes are of crucial importance to life, because a cell must separate itself from the outside environment for two major reasons. It ... of intercellular communication. The cell shields itself behind its membrane, which is relatively impermeable to most types of molecules. This barrier enables the cell to create its own intracellular ...
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