Brainscape's Knowledge GenomeTM

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


See full index

Hematology > Biochemistry > Flashcards

Biochemistry Flashcards

1
Q

what enzyme releases Fe2+ from heme

A

heme oxygenase

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

what is non-heme taken up by

A

dmt-1

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

what is the role of ceruloplasmin/hephaestin in Fe2+ metabolism

A

oxidize ferroportin that transports Fe2+ out of enterocytes

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

transcription of what enzyme is suppressed in iron deficiency anemia

A

hepcidin

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

what is the role of hepcidin

A

regulates ferroportin

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

what are the steps of iron metabolism

A

absorption and storage
recycling
uptake

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

where does heme synthesis occur

A

mitochondria then cytosol then mitochondria

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

describe heme synthesis

A

succinyl co-A and glycine form delta ALA with delta ALA synthase
delta ALA with delta ALA dehydratase gives porphobilinogen
porphobilinogen gives protoporphyrin
ferrochelatase adds Fe2+ to protoporphyrin to give heme

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

lead poisoning inhibits what enzymes in heme synthesis pathway

A

delta ALA dehydratase and ferrochelatase

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

what inhibits ALAS1 and ALAS2

A

ALAS1 inhibited by heme/hemin
ALAS2 inhibited by iron

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

what happens to the end products after heme degradation

A

biliverdin turns into bilirubin
iron is reuptaken
CO is excreted by lung

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

what happens to bilirubin upon degradation

A

degraded by bilirubin UGT
urobilinogen gives urine yellow color
stercobilin gives feces brown color

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

UROD def

A

porphyria cutanea tarda

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

symptoms of porphyria cutanea tarda

A

blistering skin lesions
elevated liver panel
tea colored urine
iron overload (no anemia)
photosensitivity

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

diagnosis and treatment of porphyria cutanea tarda

A

diagnosis: elevated uroporphyrin in urine or plasma
treatment: phlebotomy, malarial drugs

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

PBGD def

A

acute intermittent porphyria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what triggers acute intermittent porphyria

A

medication
alcohol
smoking
low glucose

18
Q

symptoms of acute intermittent porphyria

A

port wine urine
psychological disturbances
polyneuropathy
precipitated by drugs
abdominal pain

19
Q

treatment of acute intermittent porphyria

A

glucose
hemin

20
Q

ferrochelatase def

A

erythropoietic protoporphyria (EPP)

21
Q

what are the forms of hemoglobin

A

taut and relaxed form

22
Q

what does it mean when hemoglobin is in the taut form

A

low o2 affinity = releases o2 in tissues

23
Q

what does it mean when hemoglobin is in the relaxed form

A

high o2 affinity = holds on to o2 taken from lungs

24
Q

how does pH and CO2 affect oxygen affinity

A

high pH, low CO2 = high O2 affinity
low pH, high CO2= low O2 affinity

25
Q

how does 2,3 BPG affect oxygen affinity

A

it reduces oxygen affinity

26
Q

in chronic anemia, how would you describe levels of 2,3BPG

A

elevated

27
Q

how do we treat CO poisoning

A

hyperbaric oxygen therapy (100% O2 at high pressure)

28
Q

CO poisoning symptoms

A

malaise
headache
cherry red lips
nausea
dizziness

29
Q

when does HbA start to replace HbF

A

eighth month of pregnancy in bone marrow

30
Q

who has higher oxygen affinity HbA or HbF? why?

A

HbF has higher oxygen affinity because it binds weakly to 2,3 BPG unlike HbA

31
Q

how is HbA1C clinically useful

A

elevated in diabetic patients (diagnostic and monitoring)

32
Q

what is the mutation in sickle cell anemia

A

point mutation (substitution) in beta globin gene (glutamate replaced by valine)

33
Q

symptoms of sickle cell anemia

A

pain crises
hemolytic anemia
BM hyperplasia
jaundice

34
Q

what increases sickling

A

decreased pO2
increased pCO2
decreased pH
dehydration
increase 2,3BPG

35
Q

treatment of sickle cell anemia

A

blood transfusion (benefits outweigh risks)
hydroxyurea/hydroxycarbamide
stem cell transplant

36
Q

what disease is characterized by having glutamate replaced by lysine

A

hemoglobin C disease

37
Q

chocolate cyanosis is characteristic of what disease

A

methemoglobinemia

38
Q

what are the levels of alpha thalassemia

A

1: silent = asymptomatic
2: trait
3: hemoglobin H (beta4) = hemolytic anemia
4: hemoglobin bart (gamma4) = hydrops fetalis (fetal death)

39
Q

beta thalassemia minor characteristics

A

elevated HbA2
asymptomatic
mild anemia

40
Q

beta thalassemia major characteristics

A

anemia
elevated HbF
splenomegaly

41
Q

cause of sideroblastic anemia

A

mutation in ALAS2

42
Q

which enzyme is expected to be inhibited in a patient with sideroblastic anemia

A

delta ALA synthase

Hematology (4 decks)

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