metabolism

Question 1

electron exchange

Answer 1

either by transferring electrons from one atom to another; sharing electrons between atoms

Question 2

ionic chemical bond

Answer 2

formed when electrons are donated by one atom to another

Question 3

covalent chemical bond

Answer 3

formed when two atoms share a pair of electrons

Question 4

polar covalent bond

Answer 4

if one atom is more electronegative than the other the electron is shared unequally

Question 5

bond length

Answer 5

attractive and repulsive forces are in balance when nuclei separated by defined distance

Question 6

bond strength

Answer 6

measured by amount of energy needed to break that bond expressed in kilocalories

Question 7

double bond

Answer 7

four electrons can be shared; 2 coming from each atom

Question 8

ions

Answer 8

molecules carrying plus or minus charges

Question 9

hydrophobic

Answer 9

molecules are uncharged and form few or no hydrogen bonds and do not dissolve in water

Question 10

acids

Answer 10

substances that release protons to form H30+ when they dissolve in water

Question 11

bases

Answer 11

alkaline; substance that accepts protons to form OH-

Question 12

chemical bond strength

Answer 12

in water-kcal; covalent-90, ionic-3, hydrogen-1, van der waals-0.1

Question 13

electrostatic attraction

Answer 13

form between permanent dipoles-polar covalent; fully charged ions- ionic bonds

Question 14

isomer

Answer 14

molecules with the same chemical formula but different structures

Question 15

optical isomer

Answer 15

molecules that are mirror image pairs

Question 16

sugar groups

Answer 16

multiple hydroxyl groups, either one aldehyde or ketone group

Question 17

sucrose

Answer 17

disaccharide of glucose and fructose

Question 18

condensation reaction

Answer 18

molecule of water is expelled as a bond is formed between OH group on one sugar to OH group on another sugar

Question 19

hydrolysis

Answer 19

molecule of water is consumed; two monosaccharides are formed

Question 20

glycoprotein

Answer 20

smaller oligosaccharides are covalently linked to proteins

Question 21

glycolipid

Answer 21

smaller oligosaccharides are covalently linked to lipids

Question 22

fatty acid

Answer 22

hydrophylic carboxylic acid head; hydrophobic hydrocarbon chain

Question 23

saturated tail

Answer 23

no double bonds between carbon atoms

Question 24

triacylglycerol

Answer 24

consist of three fatty acid chains joined to a glycerol molecule

Question 25

phospholipid

Answer 25

cell membrane; 2 fatty acid tails; glycerol joined to phosphate group which is joined to hydrophilic polar group

Question 26

glycosidic bond

Answer 26

covalent bond between two sugar molecules

Question 27

amphiphilic

Answer 27

molecules with both hydrophobic and hydrophilic regions

Question 28

common amino acids

Answer 28

20 commonly found amino acids with n-amino beginning and c-carboxyl terminus

Question 29

L-form proteins

Answer 29

opitcal isomer form found in all eukaryotic protiens

Question 30

catabolism

Answer 30

break down food stuff generating energy

Question 31

anabolic

Answer 31

biosynthetic; drive the synthesis molecules

Question 32

second thermodynamic law

Answer 32

isolated system; the degree of disorder only increases

Question 33

entropy

Answer 33

amount of disorder in a system is quantified and expressed as this

Question 34

first thermodynamic law

Answer 34

energy can be converted but never created or destroyed

Question 35

oxidation

Answer 35

one molecule loses an electron

Question 36

reduction

Answer 36

one molecule gains an elecron

Question 37

free energy

Answer 37

measures the portion of a systems energy that can perform work

Question 38

free energy change

Answer 38

^ is change; ^G=^H-T^S

Question 39

enthalpy

Answer 39

symbolized by H; total energy in a system

Question 40

entropy

Answer 40

the randomness or disorder of a system

Question 41

spontaneous reaction

Answer 41

enthalpy must decrease or entropy must increase

Question 42

exergonic reaction

Answer 42

net release of free energy; ^G is negative, cellular respiration is example

Question 43

endergonic reaction

Answer 43

absorbs free energy; molecule synthesis

Question 44

energy coupling

Answer 44

the use of an exergonic reaction to power an endergonic reaction

Question 45

enzyme active site

Answer 45

substrate is held there by hydrogen bonds and ionic bonds

Question 46

cofactor

Answer 46

nonprotein helpers; may be bound tightly to enzyme or reversibly with substrate

Question 47

coenzyme

Answer 47

if cofactor is organic; such as vitamins

Question 48

competitive inhibitor

Answer 48

reduce the productivity of enzymes by blocking substrates from active sites

Question 49

competitive overcome

Answer 49

increase the concentration of substrate so that active sites become available

Question 50

noncompetitive inhibitors

Answer 50

bind to another part of the enzyme and impede enzymatic reactions

Question 51

irreversible enzyme inhibitors

Answer 51

often toxins and poisons that bind covalently

Question 52

allosteric regulation

Answer 52

proteins function at one site is affected by the binding of a regulatory molecule at a separate site

Question 53

enzyme cooperativity

Answer 53

binding of one substrate to active site locks all subunit active sites in active conformation

Question 54

allosteric inhibitor

Answer 54

stabilizes inactive form for one or if multiple subunits all active sites

Question 55

allosteric activator

Answer 55

stabilizes active form for one or if multiple subunits all active sites

Question 56

feedback inhibition

Answer 56

allosteric regulation where metabolic pathway is switched off by binding of product to early enzyme in the pathway