Chapter 3 - The Cellular Level of Organization Flashcards
Cell & Three components
living structural and functional units enclosed by a membrane. Membrane, nucleus, cytoplasm
Plasma membrane
flexible outer surface, separating internal from external. Regulates flow of materials and communicate.
Cytoplasm
cellular contents between plasma and nucleus, fluid portion is cytosol, within which are organelles
Nucleus
large organelle with DNA.
Fluid mosaic model
molecular arrangement of the plasma membrane resembles continually moving sea of fluid lipids that contains a mosaic of proteins
lipid bilayer
two back to back layers made up of three types of lipid molecules, phospholipids, cholesterol, and glycolipids.
phospholipid
lipids that contain phosphorous
cholesterol
a steroid with an attached OH group
glycolipid
lipids with attached carbohydrate groups
amphipathic
polar and non polar parts
Polar = phosphate head, water loving.
Not polar = hydrophobic = tails
Integral proteins
extend through lipid bilayer
transmembrane
span entire lipid bilayer, protrude into cytosol and extracellular. Amphipathic.
Glycocalyx
the carbohydrate portions of glycolipids and glycoproteins form an extensive sugary coat. Acts like signature so cells recognize each other. Basis of immune response.
Ligand
Receptors for cellular recognition, a specific molecule that binds to a receptor is called a ligand
Factors that influence diffusions rates
Steepness of the concentration gradient. Temperature. Mass of the diffusing substance. Surface area. Diffusion distance.
Aquaporins
transport water across cell membranes in response to osmotic gradients
Hydrostatic pressure
pressure of fluid on the walls. pressure of fluid in confined space
Tonicity
The ability of a solution surrounding a cell to cause that cell to gain or lose water
Isotonic solution
equal concentrations of impermeable solutes on either side of the membrane
Hypotonic solution
a solution that contains fewer dissolved particles (such as salt and electrolytes) than is found in normal cells and blood. Used to give IV
Hemolysis
rupture or destruction of red blood cells
Lysis
disintegration of a cell by rupture of the cell wall or membrane
Symporter/Antiporter
proteins that are used in transport of substances across a cell membrane. Anti=opposite direction
Diffusion
Movement of molecules or ions down a concentration gradient due to their kinetic energy until they reach equilibrium.