Chapter 3 Flashcards
What is a Plasma Membrane?
A phospholipid bilayer that surrounds a cell
is selectively permeable
What is Simple Diffusion?
Transport of molecules from an area of high concentration to an area of low concentration
passive processes, doesn’t require energy
What is Osmosis?
Transport of water from an area of high concentration to an area of low concentration
requires a membrane, is a passive process
What is Facilitated Diffusion?
Movement of certain molecules across the plasma membrane, from an area of high concentration to an area of low concentration, using specific protein channels.
* a passive process*
What is Active Transport?
Movement of molecule from an area of low concentration to an area of high concentration(against the concentration gradient).
requires energy because its active
What is Primary Active Transport?
A type of active transport that specific transport molecules (proteins) use to move specific substances across the cell membrane.
What is Secondary Active Transport?
the energy stored in a Na+ or H+ concentration gradient is used to drive other substances across the membrane against their own concentration gradients
* 2 or more molecules are moving*
What is a Symporter?
a transporter that moves two substances in the same direction
What is a Antiporter?
a transporter that moves two substances in the opposite direction
What is Endocytosis?
movement of specific ligands into a cell by forming a vesicle around that material
takes energy
What is Exocytosis?
substances are removed from the cell after a secretory vesicle fuses with the cell membrane
What is the Cytoplasm?
region between the plasma membrane and the nuclear membrane
What is the Cytosol?
the fluid portion of the cytoplasm
* its mostly water *
What are Organelles?
specific structures that perform specific functions in a cell
What is the Cytoskeleton?
a network of protein filaments
What are Ribosomes?
sites of protein synthesis
What is Rough Endoplasmic Reticulum (RER)?
a membrane that extends from the nuclear envelope
* has ribosomes imbedded into it*
What is the Smooth Endoplasmic Reticulum?
extends from the RER
* doesn’t have ribosomes*
What is the Golgi Complex?
a stack of flattened membranous sacs
its associated with protein modification and the transport of the final product
What are Lysosomes?
membrane bound sacs of digestive enzymes
What are Peroxisomes?
membrane bound sacs
contains catalase (breaks down hydrogen peroxide) and other enzymes that oxidize (removes hydrogen to deactivate) various molecules
What is the Mitochondria?
structures designed to produce large quantities of ATP
are self-replicating
How many Nucleus are in a cell?
usually one per cell
What surrounds the Nucleus?
a double membrane known as the nuclear envelope
