Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bioch sem 2 > ciclu krebs > Flashcards

ciclu krebs Flashcards

1
Q

ce este ciclul krebs

A

calea finala de oxidare a zaharidelor,lipidelor si aa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

in ce tipuri de celule se desf ?

A

celule eucariote
!!! exceptie eritrocite - NU au mitocondrii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

unde se desf ?

A

in matricea mitocondriala
in maj tesuturilor, in special in ficat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

reactia dintre Acetil CoA si H2O

A

CH3COSCoA + 3H2O -> 2 CO2 + 8H + CoA-SH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

rolul H

A

preluat de CoE
oxidare catena de transport de electroni

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

compusul esential al ciclului krebs

A

acidul oxalilacetic
rol de catalizator
intra in ciclu si se regaseste la final

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

scopul ciclului

A

generare NADH si FADH2( f reduse)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

etapa 1

A

acetil co a + oxaloacetat -> citrat + CoA- SH
enzima - citratsintetaza
proces de condensare aldolica a acetilului activat cu oxalilacetat
delta G < 0 , ireversibila

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cine inhiba citratsinteza?

A

ATP si NADH
ciclul Krebs isi adapteaza ritmul la nevoile energetice ale tesuturilor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

etapa 2

A

citrat -> isocitrat
enzima - aconitaza
se realizeaza izomerizarea acidului ciric in prezenta aconitazei prin intermediul acidului aconitic
4 Fe/ mol aconitaza
delta G =0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

etapa 3

A

isocitrat + NAD -> alfa-cetoglutarat + NADH + CO2
enzima - IZOCITRATDEHIDROGENAZA (ICDH)
produs intermediar - acid oxalilsuccinic ( se decarboxileaza pana la acid alfa-cetoglutaric)
se prod NADH si CO2!!!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

enzima NAD dependenta

A

efector alosteric pozitiv pt ADP
(NAD - f oxidata prez in mitocondrii favorizeaza TCA in scpul formarii ADP, respectiv ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

enzima NADP

A

f redusa
inhibata de crestera conc de ADP
nu fav desfasurarea TCA
(cant mari de ADP - valorile energetice ale organismului sunt satisfacute- adaptare TCA )

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ICDH

A

izocitrat dehidrogenaza
NAD dependenta (activator ADP)
NADP dependenta(inhibitor ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

determinanta de viteza

A

procese de echilibru cu viteza scazuta
influenteaza intregul proces
ex stafeta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

coenzimele NAD

A

preponderent in reactiile de oxidare din citoplasma si motcondrie
in exces f oxidata

17
Q

coenzimele NADP

A

in sinteze reductive
in exces forma redusa

18
Q

etapa 4

A

alfa-cetoglutarat + CoASH + NAD -> succinilCoA + NADH + CO2
enzima alfa-cetoglutaratdehidrogenaza
proces de decarboxilare
se prod CO2 si NADH!!!!

19
Q

etapa 4

A

alfa-cetoglutarat + CoASH + NAD -> succinilCoA + NADH + CO2
enzima alfa-cetoglutaratdehidrogenaza
proces de decarboxilare
se prod CO2 si NADH!!!!

20
Q

GDP

A

guanidindifosfat

21
Q

Pi

A

fosfat anorganic

22
Q

etapa 5

A

succinilCoA + GDP + Pi -> acid succinic + GTP + CoASH
enzima succinattiokinaza (STK)
in prezenta Mg2

22
Q

etapa 5

A

succinilCoA + GDP + Pi -> acid succinic + GTP + CoASH
enzima succinattiokinaza (STK)
in prezenta Mg2
delta G < 0

23
Q

GTP

A

guanidintrifosfat
GTP + ADP - GDP + ATP
GTP poate fi utilizat in biosinteza proteinelor,a porfirinelor, dar mai ales la obtinerea ATP din ADP

24
Q

etapa 6

A

succinat + FAD -> fumarat + FADH2
etapa caract de specificitate absoluta - se obtine un izomer (trans-fumarat)

25
Q

SDH

A

succinildehidrogenaza
metalo-enzima(Fe)
proteina intrinseca a membranei interne mitocondriale(celelalte enzime- im mitosol)

26
Q

inhibitori SDH

A

OA, acid malonic, succinimida, malonilamida

27
Q

activstori SDH

A

acid fumaric, acid succinic

28
Q

etapa 7

A

fumarat +H2O -> L-malat
enzima -fumaraza
delta G= 0

29
Q

etapa 8

A

L malat +NAD -> oxalilacetat +NADH
enzima -malatdehidrogenaza(MDH)
reactie puternic endergonica ,echilbrul deplasat mult spre stanga
delta G > 0

30
Q

in ce etape se obtine FADH?

A

etapa 6

31
Q

in ce etape se obtine NADH ?

A

3,4,8

32
Q

enzime mb ext mitocondriala

A

monoaminooxidaza
acil-coenzimsintetaza

33
Q

enzime mb int mitocondriala

A

citocromii b,c1,a,a,a3
ubichinona
succinat dehidrohenaza
ATP aza
translocaze

bioch sem 2 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions