L5 Flashcards
(87 cards)
1
Q
define metabolism
A
sum of all chemical reactions in a cell
2
Q
__ involve the transfer of electrons from an e- donor molecule to an e- acceptor, reduction = e- accepted, oxidation = e- donated, most biological oxidations involve loss of H atoms, they are also called dehydrations
A
redox reactions
3
Q
__ synthesize larger products from smaller molecules, require ATP
A
anabolism
4
Q
__ break larger products into smaller molecules, release ATP
A
catabolism
5
Q
__ sequence of chemical reactions
A
metabolic pathways
6
Q
__ flavin adenine dinucleotide
A
FAD+
7
Q
__, __, __ all are election carrier molecules used to synthesize ATP
A
NAD+, NADP+, FAD+
8
Q
__ nicotinamide adenine dinucleotide phosphate
A
NADP+
9
Q
__ nicotinamide adenine dinucleotide
A
NAD+
10
Q
In ATP production: Cells __ ADP to make __
A
phosphorylate; ATP
11
Q
What is substrate level phosphorylation
A
part of ATP production; transfer from organic compound to ATP
12
Q
describe oxidative phosphorylation
A
respiration, electrons transferred to electron carriers NAD+ and FAD
13
Q
What uses light energy to make ATP?
A
photophosphorylation
14
Q
Enzyme collision theory states that all __ are continuously moving and colliding, the energy transferred by the __ in the collision can __ the electron structures enough to break __ and form __.
A
atoms; particles; disrupt; chemical bonds; new ones
15
Q
define substrate
A
the substance an enzyme acts on
16
Q
organic catalysts that increase the likelihood of rxn w/o being permanently changed in the process, names end in -ase
A
classes of enzymes
17
Q
transfer functional groups, anabolic
A
transferases
18
Q
catabolize molecules be adding water in decomposition, hydrolysis
A
hydrolases
19
Q
split large molecule w/o using water in process
A
lyases
20
Q
rearrange atoms - do no add or remove anything
A
isomerases
21
Q
join molecules together, anabolic
A
ligases/polymerases
22
Q
What is an apoenyzme?
A
protein portion that inactive if not bound to nonprotein cofactor
23
Q
Give 4 examples of cofactors.
A
Fe, Mg, Zn, Cu, (inorganic ions)
24
Q
__ vitamins or contains vitamins - required for metabolism but cannot be synthesized
A
coenzyme
25
define ribozyme
RNA molecules acting as enzyme
26
describe activation energy
amount of energy needed to trigger a chemical reaction
27
Reaction Rate: frequency of __ sustaining enough energy to bring about reactions - depends on the __ of reactant molecules __ activation energy level, this is why heat __ the reaction rate
collisinos; number; at or above; increases
28
What is an activation site?
enzymes functional site
29
What can extremes of pH do regarding enzymes?
can denature enzymes
30
When denaturation occurs, what type of bonds break? What loses its structure?
noncovalent bonds; protein loses its structure
31
Do enzymes have optimal temperatures?
yes
32
define the turn over number
max # of substrate molecules an enzyme can convert to a product each second, usually 1-10,000 but can be as high as 500,000
33
describe the enzyme/substrate concentration
as [substrate] increases, enzyme activity increases, as more enyzmes active sites bind more substrate until reach saturation point, [enzyme] is a way to controls rxns
34
binding site on enzyme, opposite of where the substrate binds
allosteric site
35
What do inhibitors do?
block enzymes
36
describe the two types of inhibitors
competitive: fit enzyme active site and prevent normal substrate binding vs.
noncompetitive: do no bind active sites but allosteric site elsewhere on molecule and alters shape of active site
37
define feedback inhibition
use to control enzyme activity
| ex: allosteric inhibitors and metablic feedback inhibition, = end product inhibition
38
complete breakdown of glucose to carbon dioxide and water, begins with glycolysis, final electron acceptor is oxygen
cellular respiration
39
breaks down glucose and results in organic waste; what does it begin with? What is the final electron acceptor?
fermentation; begins with glycolysis; final electron acceptor is molecule made in the cell
40
In glycolysis, no __ is needed. It occurs in the __ of most cells, and has a net gain of __ ATP. Also called the __ pathway.
oxygen; cytoplasm; 2; Embden-Meyerhoff
41
In Krebs cycle, complete __ of substrate and then ATP is made through __, __ GTP, __FADH2, __NADH, __CO2, pyruvate cannot enter Krebs cycle directly, must undergo __ and lose __, the remaining __ attaches to coenzyme __ to make __, carbon dioxide fro this step and Krebs ultimately ends up in the __.
oxidation; redox rxns; 2; 2; 6; 6; decarboxylation; carbon dioxide; acetyl group; A; Acetyl CoA; atmosphere
42
Electron transport chain: series of membrane bound carrier molecules that pass __ to a final __ acceptor and create a __ pump gradient to make ATP
e-; e- acceptor; H+
43
Pentose phosphate pathway: __ sugars (__, __, and __) formed from __, are precursors to anabolic pathways, synthesis of nucleotides, net gain of __ ATP = HMP shunt which stands for __.
5c; ribulose, xyulose; ribose; glucose-6-phosphate; 1; hexose monophosphate shunt
44
Entnre-Duodoroff pathway: is a substitute for __ in some bacteria, yields precursor metabolites and __ ATP, and catabolizes glucose to pyruvate, uses different enzymes than glycolysis, also produces __NADPH, organism can metabolize glucose without __ or __ pathway.
glycolysis; 1; 2; glycolysis; pentose phosphate
45
Electron Transport Chain: energy from __ used to pump __, in cristae of __
electrons; H+; mitochondria
46
contain flavin from vit. B2 riboflavin mononucleotide (FMN) is the intitial carrier molevule
flavoproteins
47
metals alternate between reduced and oxidized, Fe-S in various organisms, Cu in those with photosynthesis
metal containing proteins
48
nonprotein carrier derived from vit. K, coenzyme A in mitochondrion
ubiquinones
49
pass electrons down the chain
carrier molecules
50
use of ion gradient to generate ATP
chemiosmosis
51
integral proteins associated with heme, Fe goes between Fell and FeIII states, carrier molecules are diverse in bacteria
cytochromes
52
proton gradient created by the oxidation of components of an electron transport chain
oxidative phosphorylation
53
protein channels that phosphorylate ADP and ATP
ATP synthases (ATPase)
54
Anaerobic respiration: final electron acceptor is an inorganic substance other than __, amount of __ generated varies with the organism and pathway, ATP yield is never as high so anaerobes grow more __ than __.
oxygen; ATP; slowly; aerobes
55
two examples of organisms that use anaerobic respiration
Pseudomonas, Bacillus, and Desulfovibrio
56
Fermentation: partial __ of sugar (or other metabolites) to release __ using an organic molecule as an __ rather than the __, oxidized __ to NAD+ and reduce organic molecules as the final electron acceptor
oxidation; energy; electron acceptor; electron transport chain; NADH
57
examples of fermentation products produced by microbes
acetic acid, ethanol, lactic acid
58
begins with glycolysis, Streptococcus and Lactobacillus, convert pyruvate to lactic acid and replenish NAD+
lactic acid fermentation
59
begins with glycolysis, pyruvate converted to acetyldehyde and then ethanol and releases carbon dioxide, replishes NAD+
alcohol fermentation
60
examples of products produced by Propionibacterium
propionic acid, used in swiss cheese
61
pathway that uses lipases to hydrolyze bonds of fatty acids to glycerol
lipid catabolism
62
What occurs in desulfurization?
removes SH group (protein catabolism)
63
Discuss protein catabolism.
most cells only catabolize proteins when carbon from glucose and fat is not available, some organisms, particularly food spoilers, normally catabolize proteins
64
Which pathway degrades fatty acids to make acetyl CoA for Krebs?
beta-oxidation
65
define deamination
removes the amine group, recycles or removes the nitrogen waste (protein catabolism)
66
What do proteases do to proteins?
split proteins into amino acids
67
What occurs in decarboxylation?
removes COOH group (protein catabolism)
68
define photosynthesis
captures light and energy and uses it to drive the synthesis of carbohydrate from carbon dioxide and water
69
captures light energy, has a hydrocarbon tail that is attached to light absorbing active site
chlorophyll
70
Where are photosystems embedded? What are they made from? What do they harvest?
embedded in thylakoids; made from chlorophyll and other pigments in protein matrix; harvest light
71
Light dependent reactions: __ light energy and use redox reactions to store energy in __ and __, and are __ on light energy.
absrob; ATP; NADPH; dependent
72
Light independent reactions: synthesizes __ from carbon dioxide and __, not __ on light energy
glucose; water; dependent
73
Describe the process of photophosphorylation.
photosystem I pigments absorb light energy and transfer it until it arrives at the reaction center chloropyll; as electrons move, the energy used to pump H+ for the proton motive force; the final electron acceptor is the original reaction center chlorophyll that donated the electron, the H+ gradient drives phosphorylation
74
Describe the process of noncyclic photophosphorlyation.
all plants and algae and some bacteria
requires photosystem I and II; light excites photosystem II; electrons are passed to photosystem I and photosystem I is energized with additional light
NADP is reduced to NADPH which is used in light independent reactions
must constantly replenish electrons to the center of photosystem II
75
Define carbon fixation.
attach carbon dioxide to ribulose 1, 5 biphosphate (Ru BP), RuBP derived from precursor metabolite of pentosephosphate pathway, substrates regenerated
76
Calvin cycle: For every __ carbon dioxides that go into Calvin cycle, __ molecule of __, 3 phosphate leaves, glycolysis is reverse to take 2 __, __ phosphates to make glucose.
3; 1; glyceraldehydes; glyceraldehyde; 3
77
list three phases of Calvin cycle
1. carbon fixation
2. reduction
3. regeneration
78
Which pathway describes reactions that can proceed either direction?
amphibolic
79
Which pathway involves an addition of an amine group?
amination
80
Which pathway uses glucose 3 phosphate as a starting point?
carbohydrate biosynthesis
81
fat synthesized in reactions that are reverse of catabolic reactions, glycerol from glucose 3 phosphate, fatty acids by linking acetyl CoA, steroid synthesis more complicated
lipid biosynthesis
82
synthesized from precursors from glycolysis, Krebs, pentose phosphate pathway, and other amino acids, essential and non essential amino acids
amino acid biosynthesis
83
What is the term for the pathway that transfers amine from 1 amino acid to another, using a coenzyme derived from B6?
transamination
84
from precursor metabolites of glycolysis and Krebs, ribose and deoxyribose from ribose 5 phosphate in pentose phosphate pathway, phosphate group from ATP, purines, and pyrimidines from glutamic and aspartic acid from Kreb's intermediates
nucleotide biosynthesis
85
control of gene =
cells control amount and timing of protein (enzyme) production
86
control of metabolic expression =
cells control activity of proteins (enzymes) once they have been produced
87
has potential energy as proton motive force used to propel down the electrochemical gradient through protein channels called ATPases
proton gradient
