AP Biology Unit 1 Test

unsaturated fats

-contains carbon to carbon double bonds in the fatty acids -C=C double bonds in the fatty acids -plant and fish fats -vegetable oils -liquid at room temp (the kinks made by double bonded C prevent the molecules from packing tightly together) -mono- and poly-

sugar polymers

-costs little energy to build -easily reversible=release energy -function: energy storage (starch in plants and glycogen in animals) and structure (cellulose in plants and chitin in arthropods and fungi)

peptide bonds

-covalent bond between NH2 (amine) of one amino acid and COOH (carboxyl) of another -C-N bond

structural isomers

-differ in covalent arrangement of atoms

starch vs. cellulose

-differ in the position of the hydroxyl group on Carbon 1 -S____ has an alpha configuration (normal bonding of glucose monomers) -C________ has a beta configuration (every other glucose monomer is upside down) -causes differences in organisms' ability to digest it (S easy, C hard)

purines

-double ring N base -adenine (A) and guanine (G)

thermal energy (heat)

-energy associated with the random movement of atoms and molecules

light energy

-energy from the sun that cane converted to solar energy, or chemical energy through photosynthesis

First Law of Thermodynamics

-energy is constant -can change forms, but cannot be created or destroyed -just like matter -"principle of conservation of energy"

potential energy

-energy not in use, but that an object possesses due to its location or structure

nucleic acid

-function: genetic material -stores information; genes, blueprint for building proteins -transfers information; blueprint for new cells and next generation -monomer: nucleotides

lipids

-functions: long term energy storage and concentrated energy, cushions organs, and insulates body -not a true polymer and not large enough to be a macromolecule -big molecules made up of smaller subunits -not a continuous chain -all mix poorly in water (hydrophobic) -include waxes, pigments, fats, pils, phospholipids, and steroids -structure: a glycerol (3 Carbons) and a fatty acid chain

pH scale

-how acidic or basic a solution is -pure water, only 1 molecule in every 554 million is dissociated -most biological fluids have 6-8 -each unit represents a 10-fold difference in H+ and -OH concentrations

noncompetitive inhibition

-if the inhibitor binds somewhere other than the active site, it blocks the substrate -binding causes the enzyme to change shape, rendering the active site unreceptive at worst or less effective at catalyzing the reaction

competitive inhibition

-if the inhibitor binds to the same site as the substrate, it blocks the substrate

cholesterol

-important cell component -animal cell membranes -helps keep membrane fluid, flexible and mobile -precursor of all other steroids ~including vertebrate sex hormones -high levels in blood may contribute to cardiovascular disease

enantiomers

-isomers that are mirror images of each other -structural differences create important functional significance

synthesis

-joins monomers by "taking" H2O out -one monomer donates -OH -other monomer donates H+ -together these form H2O -requires energy and enzymes -condensation reaction

polysaccharides

-large polymer sugars -ex: starch

floats

-less dense when it is solid, water ______ -forms crystal lattice structure -important because oceans and lakes do not freeze solid ~insulates water below ~seasonal turnover of lakes

secondary structure

-localized folding or pleating of parts of the protein chain -result of H bonds between repeating structures of polypeptide -weak bonds -α helix and β pleated sheets

nucleotides

-made up of three parts -nitrogen (C-N ring) -pentose sugar (5C) ~ribose in RNA ~deoxyribose in DNA -phosphate (PO₄) group -two types: purines and pyrimidines

cellulose

-major component of plant walls -most abundant organic compound on Earth -herbivores have evolved a mechanism to digest it -most carnivores have not evolved -undigested roughage

energy of activation

-makes the reactants unstable, increases the speed of the reactant molecules, and creates more powerful collisions -the amount of energy necessary to push the reactants over an energy barrier -at the summit the molecules are at an unstable point, the transition state

free energy

-measures the portion of a system's energy that can perform work while temperature and pressure are uniform -shows if a process or change will be spontaneous or if energy is needed for a change to occur ~negative=spontaneous ~positive or 0=not spontaneous

isomers

-molecules with the same molecular formula but different structures -different chemical properties -different biological functions

quaternary structure

-more than one polypeptide chain bonded together -only then does polypeptide become functional protein -hydrophobic interactions

proteins

-most structurally and functionally diverse group -function: involved in almost everything ~enzymes (pepsin, DNA polymerase) ~structure (keratin, collagen) ~carriers and transport (hemoglobin, aquaporin) ~cell communication (signals and receptors) ~defense (antibodies) ~movement (actin and myosin) ~storage (bean seed) -structure: ~monomer amino acids ~polymer polypeptide -can be one or more polypeptide chains folded and bonded together -large and complex molecules -complex 3D shape

phosphodiester bond

-new base added to sugar of previous base -polymer grows in one direction

cofactors

-nonprotein enzyme helpers -bind permanently to the enzyme or reversibly -ex: zinc, iron, and copper

DNA

-nucleic acid -double helix -controls its own synthesis and protégé's as well as instructions for reproduction from one generation to the next

RNA

-nucleic acid -single helix -controls protein synthesis

polar covalent bonds

-opposite ends of the molecule have opposite charges

coenzymes

-organic cofactors include vitamins or molecules derived from vitamins

evaporative cooling

-organisms use to regulate their temperature -ex: sweating -water evaporates through a surface, cooling occurs

water

-polar molecule -polar colvalent bonds -oxygen end is partial negative and the hydrogens have a partially positive end -cohesive

exergonic reactions

-release of free energy from a chemical reaction -ex: digesting polymers

phosphorylation

-released P can transfer to other molecules ~destabilizing them

geometric isomers

-same covalent relationships by different spatial arrangements

monosaccarides

-simple one monomer sugars -ex: glucose

pyrimidines

-single ring N base -cytosine (C), thymine (T), uracil (U)

hydrophilic

-some molecules have an affinity for water -polar and ionic molecules -ex: cotton, cellulose, paper

hydrophobic

-some substances do not have an affinity for water -nonpolar and non ionic substances -ex: fat, glycerol, oils

enzymes

-speed up reactions by lowering the energy barrier -regulate the movement of molecules through metabolic pathways -a catalytic protein -needed by all reactions for completion -do not change ∆G -hasten a reaction that would occur eventually -selective, determine which chemical processes will occur at any time -substrate specific -catalyze reactions only at the active site -unchanged by a reaction -can catalyze or anabolize a substrate (work towards equilibrium in reactants and products)

steroids

-structure: carbon skeleton of four fused rings with different chemicals attached -with a different functional group attached you create a new one -ex: cholesterol and sex hormones

amino acids

-structure: central carbon (alpha carbon) -amino group -carboxyl group (acid) -R group (side chain) ~variable group ~different for each ~confers unique chemical properties -physical and chemical properties based on R groups attached

phospholipids

-structure: glycerol + 2 fatty acids + PO4 (negatively charged) -contains a head and a tail region -fatty acids tails are hydrophobic -PO4 head is hydrophilic -in water, assembles into a bubble (forms a bilayer) -create a barrier for water and define "outside" vs. "inside" -make up the cell membrane

functional groups

-substitute other elements for hydrogen -parts of organic molecules that are involved in chemical reactions -give organic molecules distinctive properties -affect reactivity ~make hydrocarbons hydrophilic ~increase solubility in water

specific heat

-the amount of heat that must be absorbed or lost for 1g to change its temperature by 1C -water had high _____ due to H bonding -resists change in temp -moderates temp on earth

energy

-the capacity to cause change

∆G

-the difference between the free energy of the products and the free energy of the reactants

kinetic energy

-the energy of an object due to its motion

chemical energy

-the potential of a substance to undergo a chemical reaction and transform, thus releasing energy

thermodynamics

-the study of energy transformation

bioenergetics

-the study of how organisms manage their energy resources

metabolism

-the totality of an organism's chemical reactions -each reaction will follow a pathway -what manages the material being used and formed and the energy needed for the changes

triacylcglycerol (triglyceride)

-three fatty acid chains linked to a glycerol -combine by an Ester linkage (hydroxyl and carboxyl) -dehydration synthesis

primary structure

-unique sequence of amino acids -amino acid sequence determined by gene (DNA) -slight change in amino acid sequence can affect protein's structure and its function

digestion

-use H2O to breakdown polymers -reverse of dehydration synthesis -cleave off one monomer at a time -H2O is split into H+ and -OH -requires enzymes -releases energy -hydrolysis

energy coupling

-use exergonic (catabolic) reactions to fuel endergonic (anabolic) reactions -allows for the energy that organisms need to live

anabolism

-uses energy in order to form bonds/ molecules -go through biosynthetic pathways -dehydration synthesis

solvent

-water is the universal one -polar water molecules will surround the (+) and (-) ions causing the ions to separate and dissolve -dissolve solutes and create aqueous solutions

tertiary structure

-whole molecule folding -interactions between distant amino acids -hydrophobic interactions ~cytoplasm is water-based ~nonpolar amino acids cluster away from water -H bonds and ionic bonds -disulfide bridges ~covalent bonds between sulfurs in sulfhydryls (S-H) ~anchors 3D shape

carbohydrates

-composed of C, H, O -function: energy, raw materials, energy storage, and structural storage -monomer: sugars

disaccharides

-2 monomer sugars -ex: sucrose

cell work

-3 main types ~mechanical (muscle contractions) ~transport (diffusion/transport) ~chemical (endergonic reactions) -coupling reactions to save energy

cohesion

-H bonding between H2O creates it (sticky) -allows for the movement of water against gravity -high surface tension -water moves up a tree by transpiration (helped by ____)

adhesion

-H2O molecules form H bonds with other substances ~capillary action ~meniscus ~water climbs up fiber

neutral

-If concentration of 2 ions is equal

catalyst

-a chemical agent that changes the rate of a reaction without begin consumed by the reaction

polymer

-a long molecule consisting of similar or identical building blocks -blocks known as monomers -joined through covalent bonds -dehydration synthesis

protein structure

-a polypeptide chain that has been folded, twisted and coiled into unique shapes -performed as soon as the polypeptide is formed by creating bonds between parts of the chain -the specific structure determines the function

metabolic pathway

-a specific molecule is altered resulting in a product (needs enzymes in order to be changed)

ATP

-adenosine triphosphate -modified nucleotide -adding phosphates is endergonic -P groups unstable, excellent energy donor

saturated fats

-all carbons are bonded to hydrogens -there are no carbon to carbon double bonds -long, straight chain -most animals fats -solid at room temp. (contributes to cardiovascular disease, atherosclerosis)

Second Law of Thermodynamics

-all energy transformations increase the entropy of the universe -entropy is the measure of disorder or randomness

sugars

-all have carbonyl group and multiple hydroxyl groups -location determines whether it is an aldehyde or ketone -most names end in -ose -classified by number of carbons -when in solution, 5C and 6C structures form rings

carbon

-all life mostly based on this element -important due to its electron configuration ~able to make 4 stable covalent bonds (tetra valence) ~very versatile -tetravalence allows them to be strung together in chains

denaturation

-although proteins fold as they are made, under certain conditions, these proteins will not fold properly -can be caused by heat, change in pH, change in solution, or salinity -will be inactive -some proteins will be able to regain their original structure by removing the elements

inhibitors

-binding prevents enzymes from catalyzing reactions -binding involving covalent bonds, often irreversible -if weak, reversible

catabolism

-breaking down of complex molecules to simpler compounds -releases energy -known as hydrolysis or digestion

macromolecules

-by joining carbon to other elements, we form the basis of life -smaller organic molecules join together to form larger molecules

endergonic reaction

-chemical reaction that requires an input of energy -absorbs free energy from surroundings -ex: building polymers

hydrocarbons

-combinations of C and H -nonpolar ~not soluble in water ~hydrophobic -stable -very little attraction between molecules -gas at room temp

basic

If [-OH]>[H+]

acidic

If [H+]>[-OH]