Mcb Biochemistry Flash Cards Midterm #2- Metabolism

Front 1

kinase

Back 1

an enzyme that catalyzes the transfer of the terminal phosphoryl group of ATP to an acceptor compounds (ex. glucose or fructose 6-P)

Front 2

isozymes

Back 2

enzymes catalyzing the same reaction but encoded by different genes; there are several hexokinase isozymes (ex. II in myoctes and IV in liver)

Front 3

isomerases

Back 3

an enzyme that interconverts stereoisomers or positional isomers (e.g. Glu-6-P and Fru 6-P)

Front 4

mutase

Back 4

an enzyme that catalyzes the movement of a functional group from one position to another as in Glu 6-P to Glu 1-P

Front 5

bioenergetics

Back 5

quantitative study of energy transformations that occur in living cells, including the nature and function of chemical processes

Front 6

conservation of energy

Back 6

energy may change form or be transported but it cannot be created or destroyed

Front 7

entropy law of thermodynamics

Back 7

in all natural processes, the entropy of the universe increases

Front 8

autotrophs

Back 8

use CO2 as sole carbon source

Front 9

photoautotrophs

Back 9

obtain energy from sunlight

Front 10

chemoautrophs

Back 10

obtain energy from the oxidation of inorganic compounds

Front 11

heterotrophs

Back 11

use combined forms of carbon (sugars for carbon source and energy)

Front 12

coenzyme

Back 12

an organic cofactor required for action of certain enzymes. Often contains a vitamin

Front 13

monosaccharide

Back 13

single sugar

Front 14

disaccharide

Back 14

2 monosaccharides joined covalently by a glycosidic bond

Front 15

polysaccharide

Back 15

polymer of high MW containing monosaccharides linked covalently

Front 16

functions of carbohydrates

Back 16

1. energy release
2. energy storage
3. energy transport
4. cell structure
5. recognition signals

Front 17

fates of glucose in plants and animals

Back 17

1. storage as polysaccharide
2. oxidized to pyruvate via glycolysis
3. oxidized via pentose phosphate pathway

Front 18

importance of phosphorylation

Back 18

1. negative charge at pH 7- cannot pass membrane
2. essential for energy release in form of ATP
3. binding of P-compounds to enzymes lowers activation energy

Front 19

pathways of biosynthesis

Back 19

1. pathway for synthesis of a biomolecule is different from pathway for its degradation
2. biosynthesis and degradatory pathways are controlled by different regulatory enzymes. Initial steps of biosynthesis are regulated
3. energy requiring biosynthetic processes are coupled to the breakdown of ATP in such a way to make the overall process irreversible

Front 20

gluconeogenesis

Back 20

pathways for synthesis of glucose from 3-carbon precursors such as lactate, pyruvate, glycerol, and certain amino acids