BIOL-4610 Study Guide - Fall 2018, Comprehensive Midterm Notes - Protein, Visual Cortex, Cell Membrane
12 Oct 2018
School
Department
Course
Professor
BIOL-4610
MIDTERM EXAM
STUDY GUIDE
Fall 2018
Function of Cell Membranes and the Lipid Bilayer
Lipid bilayer: head of the phospholipid bilayer is hydrophilic and tail is
hydrophobic
Membrane = define boundary of cell and organelles
Plasma or cell membrane = Permeability barrier
Inside of cell must be physically separated from
surrounding environment
□
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○
Intracellular membrane = compartmentalize functions within
eukaryotic cells
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•
ER and Mitochondria: site of proteins
Have specific biochemical functions
Ex. Electron transport during mitochondrial respiration
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Membrane protein: control what comes in and out of cell
Gases, water, ions, nutrients and other substances = taken up into
compartments
Wastes must be removed
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Small molecules (ex. Gas) can diffuse across the membrane
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Bigger molecules (ex. Proteins) need transport proteins
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Specialized proteins detect extracellular signals
Receive info in form of electrical or chemical signals
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Signal transduction: used to describe mechanism used to
transmit signals from outer surface of cell to cell interior
Many chem signals bind to specific membrane proteins
(receptors)
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In lipid bilayer
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Allow cells to contact, adhere and communicate with other cells
Adhesive junctions
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Tight junctions: seals/block passage of fluids into cell
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Gap junctions: mediate direct cytoplasmic connection
Allow exchange of some cell components
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Plasmodesmata in plants
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Chapter 7 Membranes: Function, Structure and
Chemistry
Monday, August 27, 2018
4:37 PM
find more resources at oneclass.com
find more resources at oneclass.com
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Function of cell membranes and the lipid bilayer. Lipid bilayer: head of the phospholipid bilayer is hydrophilic and tail is hydrophobic. Membrane = define boundary of cell and organelles. Inside of cell must be physically separated from surrounding environment. Intracellular membrane = compartmentalize functions within eukaryotic cells. Membrane protein: control what comes in and out of cell. Gases, water, ions, nutrients and other substances = taken up into compartments. Receive info in form of electrical or chemical signals. Signal transduction: used to describe mechanism used to transmit signals from outer surface of cell to cell interior. Many chem signals bind to specific membrane proteins (receptors) Allow cells to contact, adhere and communicate with other cells. Tight junctions: seals/block passage of fluids into cell. Overton and langmuir: lipids are important component of membrane. Gorter and grendel: basis of membrane structure is lipid bilayer. Fluid mosaic model: membrane has two fluid layers of phospholipids + proteins inside and on the layers.
