Biol 1009 UMN exam 1 questions and answers pass guaranteed

matter - correct answers anything that takes up space and has mass, made up of elements element - correct answers cannot be broken into a simpler substance compound - correct answers substance consisting of two or more different elements in a fixed ratio eg: NaCl sodium chloride oxygen, carbon, hydrogren, nitrogen - correct answers essential elements that make up 96% of human body trace elements - correct answers required by living organisms in small quantities atom - correct answers smallest unit of matter that still retains its properties atomic nucleus - correct answers protons and neutrons at the center of the atom. atomic number - correct answers number of protons in an atom which is unique to the element. mass number, atomic mass - correct answers sum of number of protons and neutrons, mass number approximates the atomic mass. isotopes - correct answers atoms with differing numbers of neutrons. an element usually a combination of different isotopes radioactive isotope - correct answers unstable isotope where the nucleus decays spontaneously giving off particles and energy potential energy - correct answers energy possessed because of structure or location, electrons have it given their arrangement around the nucleus chemical behavior of an atom - correct answers depends largely on the number of electrons in the outermost shell valence shell valence electrons - correct answers electrons in the outer shell aka valence shell molecule - correct answers 2 or more atoms joined by a covalent bond double bond - correct answers sharing of two pairs of electrons between two atoms electronegativity - correct answers attraction of a particular atom for the electrons of of a covalent bond. - the greater the electronegativity the more strongly it pulls the shared pair of electrons towards itself. nonpolar covalent bond - correct answers the electron pair is shared equally in a covalent bond because the elements have equal E-negativity polar covalent bond - correct answers unequal sharing of the electron pair if one of the atoms is more E-neg than the other. ion - correct answers charged ion or particle. it has either gained or lost an electron. cation - correct answers positively charged ion anion - correct answers negatively charged ion ionic bond - correct answers attraction between a cation and an anion. hydrogen bond - correct answers when water molecules are close together, their positive and negative regions are attracted to the oppositely-charged regions of nearby molecules. this is a weak interaction Adhesion - correct answers clinging of one substance to another surface tension - correct answers how difficult it is to stretch or break the surface of a liquid. kinetic energy - correct answers energy of motion temperature - correct answers measure of heat intensity and also represents the average kinetic energy of molecules. heat transfer - correct answers heat passes from warmer to cooler substances until the two are the same temperature. specific heat - correct answers the amount of heat that must be absorbed or lost for 1 g of substance to change temp 1 deg C evaporation - correct answers transformation from a liquid to gas solution - correct answers homogeneous mixture of two or more substances solvent - correct answers dissolving agent within a solution solute - correct answers substance that is dissolved in the solvent. hydrophilic - correct answers any substance that has an affinity for water, colloid - correct answers large molecules that do not dissolve in water but rather remain suspended in the aqueous solution. hydrophobic - correct answers substances without an affinity for water, generally nonionic and nonpolar eg oil mole (mol) - correct answers represents the exact number of objects 6.23 * 10^23. molarity - correct answers the number of moles of solute per liter of solution acid - correct answers substance that increases the hydrogen ion concentration of a solution. base - correct answers substance that reduces the hydrogen ion concentration of a solution. isomer - correct answers compounds with the same numbers of the same elements but have a different shape and therefore different properties. light microscope - correct answers visible light passed through the specimen and then through glass lenses, which magnify the image as it is projected into the eye or into a camera. magnification - correct answers ratio of an objects image size to its real size resolution - correct answers measure of clarity of the image. it is the minimum distance two points can be separated but still distinguished. contrast - correct answers accentuates differences in the parts of a sample organelles - correct answers membrane enclosed structures within eukaryotic cells electron microscope - correct answers focuses a beam of electrons through the specimen or onto its surface. scanning electron microscope - correct answers good for the detailed study of topography . electron beam scans the surface and excites the electrons transmission EM - correct answers used to study internal structure of cells. aims an E beam through a very thin section of specimen which has been stained with heavy metals.. this has revealed many organelles. nucleoid - correct answers DNA concentrated in a region but is not bound, occurs in prokaryotic cells. "eukaryote" - correct answers means true nucleus in greek aka they have a real nucleus. cytoplasm - correct answers region generally between the nucleus and the plasma membrane. organelles are suspended in euks. cell size - correct answers eukaryotic cells tend to be larger than prokaryotic cells. plasma membrane - correct answers selective barrier found in all cells that allows for the passage of enough oxygen, nutrients, and wastes to service cell. microvilli - correct answers long thin projections from the surface which increase cellular surface area. in animal cells but not in plant cells nucleus - correct answers contains most of the genes of a eukaryotic cell. nuclear envelope - correct answers encloses the nucleus and separates the contents from the cytoplasm. this is a double membrane. envelope is perforated by pore structure chromosomes - correct answers structures that carry the genetic information. each eukaryotic species has a unique number of chromosomes chromatin - correct answers complex of DNA and proteins making up chromosomes nucleolus - correct answers -dense granules and fibers adjoining part of the chromatin. -this is where ribosomal RNA (rRNA) is synthesized. ribosomes - correct answers consist of rRNA and proteins; carry out protein synthesis. vesicles - correct answers little sacs made out of membrane material which is transports stuff endoplasmic reticulum - correct answers network of membranous tubules and sacs called cisternae. ER membrane is continuous with the nuclear envelope. smooth ER - correct answers lacks ribosomes functions include 1. synthesis of lipids 2. metabolism of carbohydrates 3. detox of drugs and poison 4. storage of calcium ions rough ER - correct answers studded with ribosomes functions include the production of secretory proteins. teh rough ER keeps these separate from proteins that will remain in the cytosol. also membrane factory of the cell by adding phospholipids and proteins to its own membrane glycoproteins - correct answers many secretory proteins are these. starch - correct answers polymer of glucose monomers as granules within cellular structures glycogen - correct answers storage within animal cells typically in the muscles or liver and releases glucose when the demand for sugar rises via hydrolysis. cellulose - correct answers major component of cell walls. can not be digested by humans microfibrils - correct answers units of cellulose molecules that are bonded chitin - correct answers used by arthropods (insects, crustaceans etc) to build their exoskeleton. types of lipids - correct answers fats, phospholipids, steroids triacylglycerols - correct answers fats or oils saturated fatty acid - correct answers as many H as possible, no double bonds. most animal fats unsaturated fatty acids - correct answers at least one double bond. double bonds are typically cis and cause a kink in the tail. polypeptides - correct answers polymer of amino acid monomers amino acid - correct answers have an amino group and a carboxyl group as well as an H and a side chain called "R" and there are many different side chains. peptide bond - correct answers resulting covalent bond between amino acids shape of protein - correct answers polypeptides spontaneously fold and assume the functioal structure of that protein. primary structure - correct answers unique linear chain of amino acids secondary structure - correct answers based off of hydrogen bonds formed b/w the repeated constituents of the polypeptide backbone alpha helix - correct answers coil held together by H bonds bw every 4th amino acid beta pleated sheet - correct answers pleats created by H bonds bw parallel polypeptide backbones tertiary structure - correct answers shape determined by the interactions of the side chains hydrophobic interaction - correct answers hydrophobic side chains tend to cluster together, held by van der waals interactions gene - correct answers unit of inheritance DNA and RNA - correct answers made up of sugar (ribose), nitrogenous bases virus - correct answers gene packaged in a protein coat and sometimes a membranous envelope. They cannot reproduce without a host genomes of viruses - correct answers can be either single or double stranded DNA or RNA and are identified as either DNA or RNA in the name viral envelope - correct answers derived from membrane of the host cell consist of host phospholipids and membrane proteins as well as glycoproteins and proteins of the virus. bacteriophages - correct answers viruses that infect bacteria host range - correct answers virus can only infect certain types of host species which are identified by a lock and key fit. restrictive enzyme - correct answers restricts the ability of a phage from infecting a bacterium. prophage - correct answers viral DNA after it has joined with the cellular DNA animal viruses - correct answers often have both a viral envelope as well as an RNA genome. the viral membrane is used to enter the host cell by binding glycoproteins on the surface RNA as viral genetic material - correct answers broadest variety of RNA genomes are found in animal viruses. retrovirus - correct answers RNA virus posess a special enzyme called reverse transcriptase and can build viral DNA from viral RNA provirus - correct answers occurs when the viral DNA is integrated into the host cell's nucleus and it remains a permanent part of the cells genome. vaccine - correct answers harmless derivative of a pathogen thta stimulates the immune system to mount defenses against the harmful pathogen. antivirals and curing viruses - correct answers antibiotics do not work on viruses. antiviral drugs - correct answers resemble nucleosides and therefore interfere with nucleic acid synthesis. epidemic - correct answers general outbreak pandemic - correct answers global outbreak viroid - correct answers circular RNA molecule that infect plants and can replicate in the host cell using host enzyme thermodynamics - correct answers study of energy transformations that occur in a collection of matter first law of thermodynamics - correct answers energy can be transferred but it cannot be created or destroyed. entropy - correct answers measures disorder and randomness second law of thermodynamics - correct answers every transfer of energy increases the entropy of the universe. spontaneous process - correct answers process can occur without expending any energy. processes with -dG nonspontaneous process - correct answers requires the input of energy, will not occur on its own. free energy - correct answers portion that can perform work when temp and pressure are held constant. exergonic reaction - correct answers proceeds with a net release of free energy. (negative dG), spontaneous endergonic reaction - correct answers process that absorbs free energy from the surroundings The 3 types of cell work - correct answers Transport, chemical, mechanical chemical work - correct answers pushing of endergonic reactions transport work - correct answers pumping of substances across the membrane against spontaneous movement mechanical work - correct answers beating of cilia , contracting muscles, movement of stuff like chromosomes. ATP Hydrolysis and how it drives work - correct answers hydrolysis of ATP is exergonic. the energy released here is able to be used to drive other chem rx which are endergonic on their own. regeneration of ATP - correct answers ATP is renewable and more of it can be made by the addition of phosphate to ADP. enzyme - correct answers macromolecule that acts as a catalyst without being consumed. activation energy - correct answers the amount of energy that must be used in order to start a reaction (contort the bonds so they break) and it is often supplied by way of thermal energy. substrate - correct answers the reactant on which an enzyme acts. active site - correct answers where the substrate binds. there must be a compatible fit bw active site and substrate. induced fit - correct answers as the substrate enters the active site the shape becomes even more snug. and brings the chemical groups into position. competitive inhibitor - correct answers mimic the substrate and try to bind at the active site, blocking the substrates and hindering the enzymes ability to catalyze. noncompetitive inhibitors - correct answers bind to another part of the enzyme, causing the enzyme to change shape slightly and this not work as well. activator - correct answers stabilizes the functional active sites inhibitor - correct answers stabilizes the inactive enzyme form. cooperativity - correct answers substrate binding to one active site triggers shape changes in all the subunits increasing catalytic activity at the other active sites. golgi apparatus - correct answers warehouse for receiving, sorting, shipping, and some manufacturing. lysosomes - correct answers membraneous sac of hydrolytic enzymes that an animal cell uses to digest (hydrolyze) macromolecules. work best in acidic environments autophagy - correct answers recycling of the cells own organic material. a damaged organelle becomes surrounded by a double membrane which then fuses with a lysosome. the organic monomers are returned to the cytosol. vacuoles - correct answers larges vesicles derived from golgi and ER. due to its selectivity, its solution has a different composition than the cytosol. mitochondria - correct answers contains out and inner membrane. the inner membrane has the mitochondrial matrix which contains mitochondrial DNA and ribosomes. the location of cellular respiration, the conversion of sugar into energy ATP chloroplasts - correct answers contain chlorophyl as well as enzymes and other molecules that participate in photosynthesis. double membrane. move along the tracks of the cytoskeleton. cytoskeleton - correct answers network of fibers extending throughout the cytoplasm along which materials travel around the cell. composed of : microtubules, microfilaments, intermediate filaments. function of cytoskeleton: provide mechanical support for the cell and help it maintain its'e shape. also provides anchorage for other organelles. microtubules - correct answers hollow tubes, shape and support the cell and serves as tracks along which organelles equipped with motor proteins can travel centrosome - correct answers microtubule organizing center located near the nucleus and . contains a pair of centrioles flagella and cilia - correct answers both are microtubule containing extensions ( flagella is like one larger tale and cilia is more like hairs) but they differ in their beating patterns microfilaments (actin filaments) - correct answers solid rods, built from actin. functions to form certain structural networks. also important is their ability to bear tension pulling forces within the cell. intermediate filament - correct answers Filaments specialized for bearing tension and are more permanent structures. (the others tend to disassemble and reassemble often) cell wall - correct answers extracellular structure of plant cells that distinguishes it from animal cell. much thicker than a plasma membrane. primary cell wall - correct answers young cell first secretes this thin and flexible cell wall middle lamella - correct answers thin layer rich in sticky polysaccharides called "pectins" and this glues adjacent cells togtether. secondary cell wall - correct answers some cells add a second cell wall (rather than just strengthening the original). collegen - correct answers most abundant glycoprotein which forms strong fibers outside the cell. proteoglycan - correct answers consists of a small core protein with many carb chains covalently attached. may be up to 95% carb fibronectin - correct answers bind to cell surface receptors called integrins that are built into the cell membrane amphipathic - correct answers having both a hydrophilic and hydrophobic region membrane proteins - correct answers reside in the the phospholipid bilayer with their hydrophilic regions protruding solidity of membrane - correct answers membrane remains fluid as temperature decreases. until the phospholipids settle into a closely packed arrangement and solidifies (think of hard grease does that too) integral proteins - correct answers penetrate the hydrophobic interior and many of them are transmembranes which span the membrane (rater than only going in partways) peripheral proteins - correct answers not embedded but rather loosely bound to the surface of the membrane, often to exposed parts of the integral proteins. channel protein - correct answers time of transport protein. creates a channel through the membrane where polar substances can pass. diffusion - correct answers movement of molecules of any substance so that they spread out evenly. this is spontaneous and requires no input of energy concentration gradient - correct answers substances diffuse from an area of higher concentration to an area of lower concentration. passive transport - correct answers diffusion of a substance across a biological membrane and no energy is expended. osmosis - correct answers diffusion of free water across a selectively permeable membrane tonicity - correct answers ability of the surrounding solution to cause a cell to gain or lose water. isotonic solution - correct answers no net movement of water across the plasma membrane because the solute concentration is the same "iso" means same hypertonic solution - correct answers "hyper" meaning m