Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Hematology > RBC and cancer metabolism > Flashcards

RBC and cancer metabolism Flashcards

(72 cards)

Start Studying
1
Q

After 120 days, RBCs aredegraded by the spleen. What causes this?

A

Inability to squeeze through splenic veins

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

What is intravascular hemolysis?

A

RBCs are damaged while circulating through the circulation

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

What is the key biological marker of intravascular hemolysis?

A

Hb

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

What is extravascular hemolysis?

A

RBCs lose their flexibility too early, and are degraded by the spleen

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

What is the key finding of extravascular hemolysis?

A

Splenomegaly

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

Why is the no serological marker of extravascular hemolysis?

A

Spleen cleans blood

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

What is the cause for sphereocytic anemia?

A

Problems with RBC membranes–cells lose their membranes, round off, and are filtered by the spleen

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

What is the cause of non-spherocytic anemia?

A

Metabolic RBC problems, leading to degradation of RBC membrane

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

What is the marker for nonsphereocytic anemia?

A

Deficiency of glycolytic or pentose phosphat pathway enzymes

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

Defect in RBC metabolism generally lead to what type of anemia (sphereocytic? intra/extravascular)?

A

nonsphereocytic hemolytic anemia, with both intra and extracellular hemolysis

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

What is the MOA of bili lights?

A

Unfolds bilirubin, increasing hydrophilicity

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

What is the cause of the limited life span of RBCs?

A

no protein synthesis

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

What is the cause of hereditary sphereocytosis?

A

Spectrin mutation leads to rounded, short liverd cells

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

What is the marker for extravascular hemolysis?

A

Bilirubin

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

What is the state that Fe needs to be kept in to be useful? What is the energy carrier molecule that is used to do this?

A

2+ (ferrous)

NADH

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

What are the two minerals that RBCs need to balance? What is the energy carrier molecule that is used to do this?

A

K and Ca

ATP

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

What protein side chain needs to be kept reduced in RBCs? What is the energy carrier molecule that is used to do this?

A

SH groups

NADPH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the four things that RBC metabolism does for the cell?

A
  1. Maintain heme
  2. Defend mineral balance
  3. Keep proteins reduced
  4. Maintain shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the two rate limiting steps in glycolysis?

A

Hexokinase reaction

PFK1 reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is glycolysis in RBCs regulated? What is the physiological consequence of this?

A

acidity (enzymes are pH dependent. Thus acidosis or alkalosis will result in hemolytic anemia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens to RBC metabolism if there is a metabolic acidosis?

A

Switch to burning lactate, to bring the pH back toward optimal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the “energy clutch” part of glycolysis of RBCs? Why is this important?

A

ability to perform glycolysis without the gain of ATP

not enough ADP to produce pyruvate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the three signs that a RBC is failing?

A

Fills with Ca
Release K
Lose biconcave shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

RBCs do not have mitochondria. What energy source is thus unable to be utilized by RBCs?

A

Fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the step that is bypassed in glycolysis for the energy clutch?
from 1,3 bisphosphoglycerate to 3 phosphoglycerate
26
Draw out glycolysis pathway, with energy clutch step.
Draw out glycolysis pathway, with energy clutch step.
27
What is the major purpose for the energy clutch step?
ATP/ADP gain is 0, get NADH
28
What are the two enzymes that are utilized in the energy clutch pathway?
Diphosphoglycerate mutase | DPG phosphatase
29
What is the intermediate that is formed between disphosphoglycerate mutase and DPG phosphatase?
2,3 BP glycerate
30
What is the role of 2,3 BPG outside of glycolysis?
maintains the T state of Hb, allowing for more oxygen delivery to tissue at lower [oxygen]
31
What is the signal for RBCs to start using the energy clutch pathway? What is the enzyme that controls this?
lower pH | PFK1
32
In cells other than RBCs, what is the enzyme that is regulated by insulin/glucagon?
PFK1
33
If the energy clutch is utilized, what is the only output of glycolysis?
NADH
34
Low pH causes increased or decreased production of 2,3 BPG? What is the effect this has on acidosis?
Reduces causes increase oxygen in the blood, increasing pH
35
What is the Bohr effect?
Lower pH will decrease Hb affinity for oxygen
36
Explain how the Bohr effect and the loss of 2,3 BPG at low pH are not at odds.
Low 2,3 BPG allows more oxygen pick up by RBCs, then as RBCs enter hypoxic tissues, will release oxygen
37
Draw out the PPP.
draw
38
What is the output of the PPP?
NADPH
39
low intracellular NADPH levels activates what enzyme to start the PPP?
glucose-6-phosphate dehydrogenase
40
What happens to the pentose products after they exit the PPP?
Reenter into glycolysis
41
Does the PPP occur in RBCs?
Yes
42
How is the PPP regulated?
Low NADPH will activate glucose-6-phosphate dehydrogenase
43
What is the protein in RBCs that prevent the oxidation of proteins?
Glutathione
44
What are Heinz bodies?
Damaged Hb
45
What is the enzyme that converts superoxide to hydrogen peroxide?
superoxide dismutase
46
Hydrogen peroxide is reduced to water by what enzyme?
glutathione peroxidase
47
The elections donated by GSH come from where?
NADPH
48
What is the enzyme that keeps glutathione in the reduced state?
Glutathione reductase (duh)
49
True or false: Genetic deficiencies usually result in intravascular hemolysis
False--usually extravascular, although less often it can be intravascular
50
G6PD deficiency is transmitted how?
X-linked recessive
51
Why is it that most pts with G6PD deficiencies do well?
Hematpoietic system is able to compensate
52
What are the symptoms of G6PD deficiency?
Jaundice with infection d/t increased bilirubin production
53
What is the food that pts with G6PD deficiency should avoid?
fava beans
54
What are the drugs that pts with G6PD deficiencies should avoid?
Those that produce ROS
55
What is the problem with pyruvate kinase deficiency?
RBCs run out of ATP, causing premature degeneration
56
What are the symptoms of pyruvate kinase deficiency?
splenomegaly Jaundice Gallstones
57
A peripheral blood stain of a pts with G6PD deficiency will show what?
Bites out of RBCs (Heinz bodies)
58
What is the major difference between pyruvate kinase deficiency and G6PD deficiency?
ROS is an issue with G6PD, while it is not for pyruvate kinase deficiency
59
A peripheral blood stain of a pts with pyruvate kinase deficiency will show what?
Blebbing of RBCs d/t loww of energy
60
What is in grey top tubes that allows for analysis of RBC metabolism? Why are these used?
sodium fluoride / potassium oxalate Fluoride inhibits enolase Oxalate is an anticoag
61
Tumor cells get most of their energy from what process? What is the substrate that they produce?
Glycolysis | Lactate
62
Why do CA cells undergo anaerobic glycolysis often?
Not enough blood supply to the tumor
63
What is the role of HIF1-alpha in tumor cells?
Increased expression increases expression of glucose transporters
64
What is the cycle whereby the liver takes up lactate and converts ito pyruvate?
Cori cycle
65
What is the name of the filament that serves as an anchor for plasma proteins in RBCs?
beta-spectrin
66
What is the name of the protein that attaches to beta spectrin, and allows for the attachment of surface proteins?
Ankyrin | band 3
67
RBC cytoskeletal defects usually present how?
As heriditary sphereocytosis
68
What is the most common cytoskeletal defect?
akyrin defect
69
Blood smears of pts with RBC cytoskeletal defects will show what?
SPhereocytes
70
What do sphereocytes look like histologically?
Round without pale center as is usualy for RBCs
71
What is the gene that causes paroxysmal noctural hemoglobinuria? What chromosome is this located on?
PIGA gene | X-chromosome
72
RBCs with the PIGA gene defect are susceptible to what? Why?
complement attack d/t loss of protein attachment

Hematology (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions