RBC Metabolism & Senescence Flashcards
(85 cards)
0
Q
High temperature shifts to what direction?
A
Right
1
Q
Low temperature shifts to what direction?
A
Left
2
Q
Do nucleated RBC replicate?
A
Yes
3
Q
Is there DNA synthesis in nucleated RBC?
A
Yes
4
Q
Is there RNA synthesis in nucleated RBC?
A
Yes
5
Q
Is there lipid synthesis in nucleated RBC?
A
Yes
6
Q
Is there heme synthesis in nucleated RBC?
A
Yes
7
Q
Are mitochondria in nucleated RBC?
A
Yes
8
Q
Are RNA present in nucleated RBC?
A
Yes
9
Q
Is there replication in reticulocytes?
A
No
10
Q
Is there DNA synthesis in reticulocytes?
A
No
11
Q
Is there RNA synthesis in reticulocytes?
A
No
12
Q
Is there lipid synthesis in reticulocytes?
A
Yes
13
Q
Is there heme synthesis in reticulocytes?
A
Yes
14
Q
Are mitochondria in reticulocytes?
A
Yes
15
Q
Are RNA present in reticulocytes?
A
Yes
16
Q
Is there replication in mature RBC?
A
No
17
Q
Is there DNA synthesis in mature RBC?
A
No
18
Q
Is there RNA synthesis in mature RBC?
A
No
19
Q
Is there heme synthesis in mature RBC?
A
No
20
Q
Are there mitochondria present in mature RBC?
A
No
21
Q
Are there RNA present in mature RBC?
A
No
22
Q
What are the functions of mature RBC?
A
Carries Hb to transport oxygen & CO2
Maintains shape & deformability
Maintains cell volume
Requires energy & generates ATP
23
Q
What are the four metabolic pathways of RBC?
A
- Embden Meyerhof
- Hexose mono-phosphate shunt
- Luebrering Rapaport pathway
- Methemoglobin reductase pathway
24
How much energy does the Embden Meyerhof pathway use?
90%
25
What is produced from the Embden Meyerhof pathway?
2 ATP
| NADH
26
What does the Embden Meyerhof convert?
Glucose to lactate
27
How much energy does the Hexose monophosphate shunt use?
5-10% of energy
28
What does the Hexose monophosphate shunt produce?
NADPH
29
In the hexose monophosphate shunt, what purpose does NADPH serve?
NADPH with glutathione are protective against oxidative damage to the cell
30
What does G-6PD deficiency cause?
Low reduced glutathione concentration
31
What does globin denatured and precipitates as?
Heinz bodies
32
A G-6PD deficiency will affect what pathway?
Hexose monophosphate shunt
33
The Luebering Rapaport Pathway produces what?
RBC organic phosphate 2,3-DPG
34
What does 2,3-DPG function in the Luebering Rapaport Pathway?
Respiratory movement
| A store of ATP
35
What pathway is responsible for producing most of the 2,3-DPG?
Luebering Rapaport
36
What metabolic pathway is responsible for 90% of the energy produced in RBC?
Emben Meyerhoff
37
A G-6PD deficiency affects glutathione processing and the cells have what?
Heinz bodies
38
The methemoglobin reductase pathway maintains what?
Heme iron in the ferrous state
39
Deficiency in the methemoglobin reductase pathway causes the buildup of what?
Methemoglobin
40
As RBC age they lose what characteristics?
Elasticity & deformability
41
What do RBC acquire as they age?
Na
IgC coating
Methemoglobin
Spheroid shape
42
What removes RBC?
Extravascular hemolysis
43
When RBCs are removed what happens to their parts?
They are stripped of their parts & salvaged
44
A small amount of RBC are removed by what?
Intravascular hemolysis
45
What is the reticuloendothelial system?
Cells in the body that take up foreign material from the blood stream & other body fluids
AKA macrophage
46
Where are macrophages present in?
```
Lymph nodes
Spleen
Bone marrow
Liver
Lung alveoli
```
47
What is another name for the reticuloendothelial system?
Mononuclear Phagocyte System (MPS)
48
What does the spleen do?
Becomes enlarged with infection
| Removes RBC, WBC, & platelets
49
What are the important parts of the GI tract?
Common bile duct
Pancreas
Pancreatic duct
50
What are the components of Heme?
Globins
Iron
Heme
51
Where are the RBC removed and the parts are stripped and salvaged?
In the reticuloendothelial system (RES)
52
In extravascular hemolyis, what are broken down into amino acids & salvaged?
Globins
53
In extravascular hemoysis, what is transported by Transferrin back to bone marrow?
Iron
54
In extravascular hemolysis what is dimantled and degraded?
Heme
55
What happens to the globins, iron, and heme in extravascular hemolysis?
Globins - broken down to amino acids & salvaged
Iron - transported by Transferrin back to bone marrow
Heme - dismantled & degraded
56
The open tetrapyrrole ring of heme is cleaved into ____ which is converted to _____, bound to ______ & carried to the liver.
Biliverdin
Bilirubin
Albumin
57
Is bilirubin conjugated or unconjugated?
Unconjugated
58
In the liver bilirubin is conjugated to _______ & excreted in bile to the intestines.
Bilirubin glucoronide
59
Is bilirubin glucoronide conjugated or unconjugated?
Conugated
60
In the intestines bilirubin glucoronide is converted to _____ & excreted in the stool or reabsorbed & later excreted in the urine.
Urobilinogen
61
Explain the process of extravascular hemolysis.
Globin & iron portions of the molecule are conserved & reutiilized. Heme is reduced to bilirubin & eventually degraded to urobilinogen, & excreted into the feces. Indirect indicators of erythrocyte destruction include the blood bilirubin level & urobilinogen concentration in the urine.
62
The first bilirubin metabolite produced by destruction of heme is?
Biliverdin
63
Bilirubin in the circulation must be bound to?
Albumin
64
Bilirubin glucuronide is stored in the gall bladder and?
Shipped to the small intestine
65
Bacteria in the intestine convert bilirubin-glucuronide to?
Urobilinogen
66
Elevated Urobilinogen in the urine indicates increased hemolysis - T/F
True
67
Intravascular hemolysis accounts for what percentage of RBC destruction?
5-10%
68
Hemoglobin released into blood stream is toxic to the kidney - T/F
True
69
Alpha & beta globins bind to what?
Haptoglobin
70
In intravascular hemolysis, _______ is transported to liver.
Haptoglobin-hemoglobin
71
A ______ ______ indicates intravascular hemolysis/
Decreased haptoglobin
72
A decreased haptoglobin indicates _____ ____.
Intravascular hemolysis
73
After haptoglobin is depleted in urine, free hemoglobin dimers appear in plasma as _____ & are filtered through the kidneys as _____.
Hemoglobinemia
| Hemoglobinuria
74
Plasma can be what colors?
Red, pink, or brown
75
Urine may be what colors?
Pink, red brown, or black
76
What color is oxyhemoglobin?
Red, usually in alkaline urine
77
When urine is red, what type of hemoglobin is it?
Oxyhemoglobin
78
What color is methemoglobin?
Brown, usually in acid urine
79
In acid urine, what type of hemoglobin is present?
Methemoglobin
80
Free metheme in the circulation binds to what?
Hemopexin
81
What are laboratory indicators of hemolysis?
Total bilirubin
Conjuagted (direct) bilirubin
Urine urobilinogen
Haptoglobin
82
What is decreased following intravascular hemolysis?
Haptoglobin
83
Blood in intravascular hemolysis are what shape?
Schistocytes
84
Blood in extravascular hemolysis are what shape?
Spherocytes
