3.1 The Cell Membrane Flashcards
Cell Membrane
an extremely pliable structure composed primarily of back-to-back phospholipids (a “bilayer”)
an extremely pliable structure composed primarily of back-to-back phospholipids (a “bilayer”)
Cell Membrane
Hydrophilic Molecule
is attracted to water
is attracted to water
Hydrophilic Molecule
Hydrophobic Molecule
repelled by water
repelled by water
Hydrophobic Molecule
Amphipathic Molecule
contains both a hydrophilic and a hydrophobic region
contains both a hydrophilic and a hydrophobic region
Amphipathic Molecule
Phospholipid Structure Reference
Intracellular Fluid (ICF)
the fluid interior of the cell
the fluid interior of the cell
Intracellular Fluid (ICF)
Extracellular Fluid (ECF)
the fluid environment outside the enclosure of the cell membrane
the fluid environment outside the enclosure of the cell membrane
Extracellular Fluid (ECF)
Interstitial Fluid(IF)
the term given to extracellular fluid not contained within blood vessels
the term given to extracellular fluid not contained within blood vessels
Interstitial Fluid(IF)
Phospholipid Bilayer Reference
Integral Protein
a protein that is embedded in the membrane
a protein that is embedded in the membrane
Integral Protein
Channel Protein
is an example of an integral protein that selectively allows particular materials, such as certain ions, to pass into or out of the cell
is an example of an integral protein that selectively allows particular materials, such as certain ions, to pass into or out of the cell
Channel Protein
Cell Membrane Reference
Receptor
protein molecule that contains a binding site for another specific molecule (called a ligand)
protein molecule that contains a binding site for another specific molecule (called a ligand)
Receptor
Ligand
molecule that binds with specificity to a specific receptor molecule
molecule that binds with specificity to a specific receptor molecule
Ligand
Glycoprotein
protein that has one or more carbohydrates attached
protein that has one or more carbohydrates attached
Glycoprotein
Glycocalyx
coating of sugar molecules that surrounds the cell membrane
coating of sugar molecules that surrounds the cell membrane
Glycocalyx
Peripheral Proteins
membrane-associated protein that does not span the width of the lipid bilayer, but is attached peripherally to integral proteins, membrane lipids, or other components of the membrane
membrane-associated protein that does not span the width of the lipid bilayer, but is attached peripherally to integral proteins, membrane lipids, or other components of the membrane
Peripheral Proteins
Selective Permeability
feature of any barrier that allows certain substances to cross but excludes others
feature of any barrier that allows certain substances to cross but excludes others
Selective Permeability
Passive Transport
the movement of substances across the membrane without the expenditure of cellular energy
is the movement of substances across the membrane without the expenditure of cellular energy
Passive Transport
Active Transport
the movement of substances across the membrane using energy from adenosine triphosphate (ATP)
the movement of substances across the membrane using energy from adenosine triphosphate (ATP)
Active Transport
Concentration Gradient
difference in the concentration of a substance between two regions
difference in the concentration of a substance between two regions
Concentration Gradient
Diffusion
movement of a substance from an area of higher concentration to one of lower concentration
movement of a substance from an area of higher concentration to one of lower concentration
Diffusion
Simple Diffusion
molecules moving across a cell membrane from the side where they are more concentrated to the side where they are less concentrated
molecules moving across a cell membrane from the side where they are more concentrated to the side where they are less concentrated
Simple Diffusion
Simple Diffusion Reference
Facilitated Diffusion
the diffusion process used for those substances that cannot cross the lipid bilayer due to their size, charge, and/or polarity
the diffusion process used for those substances that cannot cross the lipid bilayer due to their size, charge, and/or polarity
Facilitated Diffusion
Facilitated Diffusion Reference
Osmosis
the diffusion of water through a semipermeable membrane
the diffusion of water through a semipermeable membrane
Osmosis
Osmosis Reference
Isotonic (equal tension)
two solutions that have the same concentration of solutes
two solutions that have the same concentration of solutes
Isotonic (equal tension)
Hypertonic
a solution that has a higher concentration of solutes than another solution
a solution that has a higher concentration of solutes than another solution
Hypertonic
Hypotonic
a solution that has a lower concentration of solutes than another solution
a solution that has a lower concentration of solutes than another solution
Hypotonic
Concentration of Solutions Reference
Sodium-Potassium Pump (Na+/K+ ATPase)
transports sodium out of a cell while moving potassium into the cell
transports sodium out of a cell while moving potassium into the cell
Sodium-Potassium Pump (Na+/K+ ATPase)
Electrical Gradient
a difference in electrical charge across a space
a difference in electrical charge across a space
Electrical Gradient
Sodium-Potassium Pump Reference
Endocytosis (bringing into the cell)
import of material into the cell by formation of a membrane-bound vesicle
import of material into the cell by formation of a membrane-bound vesicle
Endocytosis (bringing into the cell)
Vesicle
membrane-bound structure that contains materials within or outside of the cell
membrane-bound structure that contains materials within or outside of the cell
Vesicle
Phagocytosis (“cell eating”)
the endocytosis of large particles
the endocytosis of large particles
Phagocytosis (“cell eating”)
Pinocytosis (“cell drinking”)
brings fluid containing dissolved substances into a cell through membrane vesicles (endocytosis of fluid)
brings fluid containing dissolved substances into a cell through membrane vesicles (endocytosis of fluid)
Pinocytosis (“cell drinking”)
Three Forms of Endocytosis Reference
Receptor-Mediated Endocytosis
is endocytosis by a portion of the cell membrane that contains many receptors that are specific for a certain substance
is endocytosis by a portion of the cell membrane that contains many receptors that are specific for a certain substance
Receptor-Mediated Endocytosis
Exocytosis (taking out of the cell)
is the process of a cell exporting material using vesicular transport
is the process of a cell exporting material using vesicular transport
Exocytosis (taking out of the cell)
Exocytosis Reference
