Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Bio-Cell &Metabolism
Chapters 6-8
| Question | Answer |
|---|---|
| light miscroscopes | visible light is passed through the specimen and then through glass lenses. lenses refract light so that image of specimen is magnified. |
| magnification | ratio of an object's image size to its real size |
| resolutions | measure of clarity of the image |
| what can you see with light microscopes | (1 cm to 100 nanometers). most plant and animal cells, the the nucleus, most bacteria and mitochondria |
| organelles | membrane enclosed compartments, to small to be seen by light microscopes |
| electron microscopes | focuses a beam of electrons through specimen or onto its surface. (100 micrometers to .1 nanometers) can see most plant and animal cells to small molecules and atoms |
| scanning electron microscope | used for detailed study of the surface of a specimen. electron beam scance the surface of the sample |
| transmissions electron microscope | used to stduy the internal ultrastrucuture of cells |
| cell fractionation | takes cells apart and separates the major organelles and other subcellular structures from one another. instrument used is the centrifuge that spins test tubes at various speeds until the cell is disrupted |
| what do all cells have in common | plasma membrane, cytosol, chromosomes, and ribosomes |
| what is the major difference between eukaryotes and prokaryotes concerning dna | eukaryotes carry dna in nuleus, a double membrane structure. prokaryotes carry dna in nucleoid which is not membraned. |
| cytoplasm | interior of prokaryotes and region between nucleus and plasma membrane in eukaryotes |
| cell size | limits set by metabolic requirements (upper limit) but surface area to volume ratio sends limit on lower limit as well as plasma membrane which lets things in and out |
| nuclear envelope | encloses nucleus, separating contents of nucleus from the cytoplasm. double membrane. has pore complex of proteins that regulates entries and exits of proteins and RNA |
| nuclear lamina | netlike array of protein filaments that maintains shape of the nucleus by mechanically supporting nuclear enevelope |
| chromosomes vs chromatin | chromosomes carry dna. however when in nucleus is just chromatin (noodle like mess). when cell begins to divide they coil up to become chromosomes |
| nucleolus | densely stained granules and fibers adjoining part of the chromatin. ribosomal RNA is synthesized here. assemble proteins into ribosomal units |
| ribosomes | complexes made of ribosomal RNA and proteins. in charge of protein synthesis |
| free ribosomes vs. bound | free are suspended in cytosol and bound are attached to outside of ER or nuclear envelope. structures are simliar |
| ER | synthesis of proteins and their transport. metabolism and movement of lipids, and detoxification of poisons. extensive network of membranes |
| vesicles | membrane segments (sacs of membranes) |
| smooth er | have enzymes are important in synthesis of lipids. have enzymes that detoxify drugs. metabolism of carbs |
| detoxification | usually involved adding hydroxyl group |
| rough er | have ribosomes. cells secrete proteins produced by ribosomes attached to rough er |
| glycoproteins | have crabohydrates covalently bonded to them. |
| transport vesicles | membrane sacs that carry proteins or other nutrients |
| golgi apparatus | manufacturing, warehousing, sorting, and shipping. stack of membrane structure. cis face is located near er so transport vesicles can move between the two. trans face gives rise to vesicles which pinch off to other parts of the cell |
| lysosomes | membranous sac of hydrolytic enzymes that an animal cell uses to digest macromolecules. intrcellular digestion |
| phagocytosis | food vacuole formed and fuses with lysosomes. |
| pinocytosis | vacuole for water |
| contractile vacuoles | found in freshwater protists that pump water excess water out of cell. |
| central vacuole | mature plant cells. holds reserve of important organic compounds |
| mitochondria | sites of ecllular respiration, metabolic process that generates ATP. |
| chloroplasts | found in plants, sites of photosynthesis. enclosed by membranes |
| endomembrane system | flow of membrane lipids and protein. the er, golgi, plasma membrane, and lysosomes |
| mitochondria structure | smooth outer membrane. convoluted infolded inner membrane called cristae. |
| mitochondrial matrix | enclosed by inner membrane. has enzymes, specific mitochondrial dna, and ribosomes. |
| chloroplasts | has an outer membrane, and within the chloroplast is the thylakoids (poker chips). granum (stacks of poker chips). fluid outside thylakoid is stroma which contains chloroplast DNA and ribosomes with enzymes |
| cytoskeleton | network of fibers extending throughout the cytoplasm. mechanical support to cell shape |
| microtubules | hollow tubes that aid in chromosome movement in cell division and organelle movements. (cell shape and cell motility) |
| microfilaments | two intertwined strands of proteins. changes in cell shape. cytoplasmic streaming. cell division and motility and shape |
| intermediate filaments | fibrous proteins supercoiled into cables. cell shape, anchorage of nucleus and other organelles, formation of nuclear lamina |
| centrosomes | contain centrioles, aid in cell division |
| cilia and flagella | appendages that stick out of cell. flagella the funky tail, and cilia is the waving grass like structure |
| cell wall | plant cells. maintains cell shape and prevents excessive water from being taken. has primary wall (actual wall) middle lamella (sticky stuffy between plant cells) and secondary cells wall (right outside plasma membrane before primary) |
| metabolism | totality of an organism's chemical reactions |
| metabolic pathway | begins with a specific molecules that is then altered in a series of defined steps, resulting in a certain product. each step is catalyzed by a specific enzyme |
| catabolic pathways | metabolic pathways that release energy breaking down complex molecules into simpler compounds. cellular respiration |
| anabolic pathways | consumes energy to build complicated molecules from simpler ones. biosynthetic pathways |
| energy | capacity to change |
| heat or thermal energy | is a type of kinetic energy associated with random movements of atoms or molecules |
| chemical energy | potential energy available for release in a chemical reaction |
| thermodynamics | study of energy transformation that occur in collection of matter. system is actual thing being studied, surrounding is surrounding of system |
| first law of thermodynamics. principle of conservation of every | energy of universe is constant. energy can be transferred and transformed but it cannot be created or destroyed |
| forms of energy | kinetic and potential |
| can all energy be used over and over again | in most energy transformations some energy becomes unusable and unavailable to do work. more usable forms oof energy is often converted to heat--random motion of atoms and molecules. heat only works if it moves from warm to cool areas |
| second law of thermodynamics | every energy transfer or transformation increases the entropy of the universe |
| entropy | meausure of disorder or randomness |
| free energy | portion of a system's energy that can perform work when temperature and pressures are uniform throughout the system as in a living cell. |
| exergonic reaction | proceeds with a net release of free energy |
| endergonic reaction | absorbs free energy from its surroundings |
| chemical work | pushing of endergoic reactions such as synthesis of polymers from monomers. |
| transport work | pumping of substances across a membranes against the direction of spontaneous movement |
| mechanical work | beating of cilia, contraction of muscle cells, and movement of chromosomes during cellular reproduction |
| energy coupling | use of exergonic process to drive an endergonic one. |
| ATP | sugar ribose, nitrogenous base adenine, and a chaine of three phosphate groups. |
| hydrolysis of ATP | bonds between phosphate groups of ATP can be broken by hydrolysis. when the last phosphate bond is broken an inorganic phosphate molecules leaves the ATP, which becomes ADP. reaction is exergonic and releases energy |
| why does ATP release energy | all 3 phosphate groups are negatively charged. the like charges are crowded together and their mutual repulsions contributes to the instability of the ATP molecule. |
| phosphorylated | when the phosphate groups from atp is received by some other reactant. d |
| how does atp couple exergonic and endergonic reactions | it releases energy when broke apart to create adp and phosphate group, but it absorbs energy when creating atp with adp and phosphate group. |
| what is uniqe about atp | reusable and recycable |
| enzymes | enzymes are macromolecules that ac as catalysts, which speeds up reaction which being consumed by the reaction |
| activation energy | initial investment of energy for starting a reaction. often supplied as heat that reactants absorb from environment to speed up reactions |
| activation energy hill | the activation energy is represented by the uphill portion of the graph, at the summit is where the reactants are in an unstable condition known as transition state. they are activated, bonds are broken, bond forming happens during downhill part of curve |
| enzymes lower activation energy barrier | enable reactant molecules to absorb enough energy to reach transition state even at moderate temperatures. enzymes cannot change the free energy for a reaction, they can only speed up the process |
| substrate | the molecules the enzyme works on |
| products | the molecules formed by the enzyme substrate complex |
| active site | pocket or groove on the surface of the enzyme that binds to substrate |
| specificity of enzymes | compatible fit between shape of its active site and the shape of the substrate |
| induced fit | brings chemical groups of the active site into positions that enhance the ability to catalyze the chemical reaction |
| first step of catalysis | substrates enter active site. enzyme changes shape such that its active site enfolds the substrate |
| in catalysis what happens after the substrate enters active site | substrates held in active site by weak interactions |
| in catalysis what happens after substrates are held by active site | active site can lower activation energy barrier & speed up reaction by acting as a template for substrate orientation. stressing the substrates and stabilizing the transition state. providing favorable microenvironment. participating directly to reaction |
| what happens after enzyme lowers activation energy barrier | substrates are converted to products and products are released |
| what are two factors that affect enzyme activity | temperature and pH. enzymes have optimal temperature and optimal pH. exceeding that optimal environment the enzyme can denature and lose its shape |
| cofactors | adjuncts that help with catalytic activity. can be tightly bound permanently or loosely bound. often called coenzymes |
| inhibitors | they change the action of a specific enzymes. if they are bound covalently then they are irreversible but if they have weak interactions then its irreversible |
| competitive inhibitors | mimic the normal substrate molecules and compete for admission to active site. they reduce productivity of enzymes by blocking substrates from entering active sites. can be overcome with increased concentration of substrates as opposed to inhibitors |
| noncompetitive inhibitors | do not directly compete with substrate to bind to active site. impede enzymatic reactions by binding to another part of the enzyme. interaction causes enzyme to change shape so that active site becomes less effective at catalyzing the substrate |
| allosteric regulation | enzyme's function at one site is affected by the binding of a regulatory molecule to a separate site. it may result in either inhibition or stimulation of an enzyme's activity |
| binding of activators vs inhibitors | the binding of an activator to an allosteric site (regulatory site) stabilizes shape that has functional active site. binding of an inhibitor stabilizes the inactive form of an enzyme |
| cooperativity | if an enzyme has two or more subunits, a substrate molecules causing induced fit in one subunit can trigger the same favorable shape change in all the other subunits of the enzyme. amplifies response of enzymes to substrates. |
| feedback inhibition | a metabollic pathway is switched off by the inhibitory binding of its end products to an enzyme that acts early in the pathway. when ATP allosterically inhibits enzyme in ATP generating pathway. |
| selective permeability | allows som substances to cross it more easily than others |
| amphipathic molecule | it has both a hydrophilic region and hydrophobic region |
| fluid mosaic model | membrane is a fluid structure with a "mosaic" of various proteins embedded in or attached to a double layer (bilayer) of phospholipids. |
| how can proteins easily fit into the phospholipid bilayer | the interior and middle of the protein, near the hydrophobic tailm is hydrophobic . while the parts of the protein that are near the outside of the bilayer are hydophilic. hydrophobic regions of protein have nonpolar amino acids coiled into helixes |
| membrane fluidity | membranes remain fluid until temp decreases enough for it to solidify. when membranes solidigy, its permeability changes and enzymatic proteins cannot work properly. |
| integral proteins | penetrate the hydrophobic core of the lipid bi layers. |
| transmembrane proteins | span the membrane, other integral proteins extend only partway into the hydrophobic cores |
| peripheral proteins | not embedded in the lipid bilayer at all; are appendages looselyy bound to the surface of the membrane. often exposed to parts of integral proteins |
| glycoproteins | cell to cell recognition. have carbohydrates attached to them |
| glycolipids | carbohydrates covalently bonded to lipids |
| transport proteins | channel proteins that can help hydrophilic substances pass through lipid bilayer. have hydrophilic channel |
| aquaporins | passage of water molecules through membranes is facilitated by aquaporins. |
| diffusion | movement of molecules of any substance so that they spread out evenly into the available space. |
| concentration gradient | region along which the density of a chemical substane decreases. high to low |
| passive transport | diffuseion of a substance across a biological membrane, cell does not have to expend energy to make it happen. often follow concentration gradient. |
| osmosis | diffusion of water |
| isotonic | no net movement. at equilibrium. normal animal cell and flaccid plant cell (limp) |
| hypertonic | solution has more sugar, water will move out of cell and cell will shrivel. shriveled animal cell ad playmolyzed plant cell (plant cell shrivel and die) |
| hypotonic | solution has less sugar, water will move into cell and burst. animal cell lysed and turgid pressure created in plant cell (firm) |
| facilitated diffusion | passive diffusion. no work is done |
| ion channels | facilitated diffusion that have gated channels that open and close according to stimuli |
| active transport | proteins need energy to get molecules across the membrane often against concentration gardient/ |
| sodium potassium pump | exchanges sodium with potassium across the membrane. sodium binds to pump, atp gets used, changes shape of protein, releases sodium, brings in potassium. protein loses phosphate group which triggers shape change of protein and release of potassium |
| cotransport | single atp powered pump that trasnports a specific solute can indrectly drive the active transport of several other solutes. proton pump actively transports H+ outside cell. h+ gradient goes through sucrose co trasnporter drives intake of sucrose |
| exocytosis | fusions of vesicles that secrete nutrients outside the cell |
| endocytosis | intake of substance by vesicles |
| phagocytosis | cellular eating |
| pinocytosis | cellular drinking |
| receptor mediated endocytosis | certain recepers on the plasma membrane attract certain molecules to take in. |
Created by:
LittleD331
Popular Biology sets