chapter 5 & 6 Flashcards
the energy of motion
kinetic energy
energy that is not being used, but could be; energy in a potentially usable form; “energy of position”
potential energy
the energy contained within a system that is responsible for its temperature
thermal energy
a measure of the random motion of molecules; the greater the heat, the greater the motion
heat
energy cannot be created or destroyed, but can undergo conversion from one form to another; thus the amount of energy in the universe is unchangeable
first law of thermodynamics
statement concerning the transformation of potential energy into heat; it says that disorder is continually increasing in the universe as energy changes occur, so disorder is more likely than order
second law of thermodynamics
the region of an enzyme surface to which a specific set of substrates binds, lowering the activation energy required for a particular chemical reaction and so facilitating it
active sites
an inhibitor that binds to the same active site as an enzyme’s substrate, thereby competing with the substrate
competitive inhibitor
the diffusion of molecules or ions through carrier proteins or ion channels, requires a concentration gradient, but not any input of energy
facilitated diffusion
a solution with a higher concentration of solutes than the cell - cell loses water by osmosis
hypertonic
a solution with a lower concentration of solutes than the cell - cell takes in water by osmosis (cell explodes)
hypotonic
movement of substances across a cell’s membrane without the expenditure of energy
passive transport
a difference in concentration inside the membrane verses outside
concentration gradient
the net movement of dissolved molecules or other particles from a region where they are more concentrated to a region where they are less concentrated
diffusion
the energy that must be processed by a molecule in order for it to undergo a specific chemical reaction
activation energy
the foundation to which an organism is attached; molecule on which an enzyme acts
substrate
the complex formed when an enzyme binds with its substrate - this complex often has an altered configuration compared with the non-bound enzyme
enzyme-substrate complex
requires an input of energy to synthesize complex molecules from similar ones (small molecules assemble into larger ones)
anabolic pathway
involves the degradation or break down of complex molecules into simpler ones -energy is released
catabolic pathway
linked series of chemical reactions occurring within a cell
metabolic pathway
an inhibitor that binds to a location other than the active site of an enzyme, changing the enzyme’s shape so that it cannot bind the substrate
noncompetitive inhibitor
a protein that is capable of speeding up specific chemical reactions by lowering the required activation energy
enzyme
a stable condition; the point at which a chemical reaction proceeds as rapidly in the reverse direction as it does in its forwarddirection
equililbrium
energy available for work
free energy
describes a chemical reaction in which the products contain more energy than the reactants, so that free energy must be put into the reaction from an outside source to allow it to proceed
endergonic reaction
describes a chemical reaction in which the products contain less free energy than the reactants, so that free energy is released into the reaction
exergonic reaction
membrane channel that allows water to cross the membrane more easily than by diffusion through the membrane
aquaporins
the pumping of ions or other molecules across a cellular membrane from a region of lower concentration to one of higher concentration; this transport process requires energy
active transport
solution having the same concentration of solutes as the cell - cell takes in/loses the same amount of water
isotonic
diffusion of water across a selectively permeable membrane; in the absence of differences in pressure or volume - the net movement of water is from the side containing a lower concentration of solute to the side containing a higher concentration
osmosis
protein molecules notified within the golgi complex by having a short sugar chain (polysaccharide) attached
glycoprotein
lipid molecule notified within the golgi complex by having a short sugar chain attached
glycolipid
similar in structure to fat - having only two fatty acids attached to the gylcerol backbone, 3rd space linked to a phosphorlated molecule
phospholipid
describes the cell membrane as a tapestry of several types of molecules (phospholipids, cholesterols, and proteins) that are constantly moving
fluid mosaic
two types of proteins that are embedded in the plasma membrane and what is the difference between them
integral proteins - embedded in the whole bilayer
peripheral proteins - located on the inner or outer surface
proteins that transport substances across biological membranes (two types)
transport proteins
-facilitated diffusion
-active transport
what are the four components of a cellular membrane? (describe)
a. phospholipid bilayer (flexible matrix - barrier to permeability)
b. transmembrane proteins (integral membrane proteins)
c. interior protein network (peripheral or intracellular membrane proteins)
d. cell-surface markers (glycoproteins/glycolipids)
allows some substances to cross membrane more easily than others
selective permeability
hydrophillic and hydrophobic portions in their structure - what is this called?
amphiphatic
substances that accomplish catalysis-process of influencing chemical bonds in a way that lowers the activation energy needed to initiate a reaction
catalyst
process that occurs naturally- requires no energy input
spontaneous reaction
will not take place - unless it is “driven” by the continually input of energy from an external source
nonspontaneous reaction
the uptake of material into cells by inclusion within an invagination of the plasma membrane; the uptake of solid material is phagocytosis -dissolved material is pinocytosis
endocytosis
type of bulk transport of cells in which a vacuole fuses with the plasma membrane discharging the vacuole’s contents to the outside
exocytosis
(our card from class)
what is the function of an enzyme? and example of it :)
function: a protein that is capable of speeding up specific chemical reactions by lowering the required activation energy
bodies naturally makes enzymes without them our bodies would not function at all.
example:
amylase -> saliva help change starches into sugars
pepsin -> stomach enzyme digests proteins found in ingested foods
