Brainscape's Knowledge GenomeTM

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


See full index

BioChem Exam 3 > Blood > Flashcards

Blood Flashcards

1
Q

3 basic components of blood?

A

Plasma/serum

Buffy coat

Erythrocytes

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

Main components of plasma?

A

Water 92%

Proteins 7%
Albumins mostly, 
Globulins
Fibrinogen
Regulatory proteins

Other solutes 1%
Electrolytes, Nutrients, Respiratory gases, Waste products

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

Components of buffy coat?

A

Platelets, WBCs

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

What is serum?

A

Liquid component of clotted blood

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

What is plasma?

A

Unclotted blood = all mixed together..RBCs, liquids, proteins, platelets

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

Most abundant non cellular protein in blood? Function?

A

Albumin

=> secreted by hepatocytes as carrier proteins
=> maintains oncotic pressure
=> helps keep fluid from leaking out

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

Hypoalbuminemia causes?

A

Through liver failure => fluid leaking => oncotic pressure falls

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

Second most common type of protein in blood?

A

Immunoglobulins

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

Where does heme synthesis take place?

A

Mitochondria and cytosol

=>liver

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

First and limiting step of heme synthesis in mitochondria?

A

Glycine + Succinyl-CoA –ALA synthase–> delta-ALA

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

Which enzyme is deficient in what disease causing the absence of Protoporphyrin IX?

A

Proto-porphyrinogen oxidase

=> variegate porphyria

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

Lack of Protoporphyrin IX causes?

A

Sideroblastic anemia

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

What are prophyrias?

A

Genetic diseases resulting in decreased activity of one+ enzymes involved in heme synthesis

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

How many O2 can Hgb bind?

A

Maximum of 4

But usually isn’t 4

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

Recognize structures on slide 8

A

K

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

What is anemia?

A

Quantity of RBCs = lower than normal => capacity of blood to carry adequate O2 is compromised

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

What causes anemia?

A

Failure to produce enough RBCs (iron deficiency=most common cause/aplastic anemia)

Loss of RBCs (hemorrhaging)

Increased destruction of RBCs that can not be compensated for by bone marrow (sickle cell anemia/autoimmune hemolytic anemia)

Sequestration of RBCs (spleen)

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

Why does CO have a 200x greater affinity for Hgb than O2?

A

CO is unstable => lone electron pair on positively associated carbon => gains stability by binding to Hgb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Diseases of inadequate Hgb synthesis?

A

Porphyrias

Hemoglobinopathies (thalessemias, sickle cell anemia)

Iron deficiency anemia

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

What is hemoglobinopathies? Whats the specific change leads to thalessemia?

A

Problem with hemoglobin synthesis => disorder of one of globin side chains of hemoglobin

Thalessemias => wrong amount of globin chains => 4 alpha-gene an 2 beta-globin genes

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

What kind of genetic mutation leads to thalessemia?

A

Frameshift or nonsense mutation

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

What is alpha-Thalessemia?

A

Underproduction of alpha-globin due to mutated alpha-globin genes

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

Sub-types of alpha-thalessemia?

A

Carrier: one alpha-globin gene mutated -> no clinical manifestations

Alpha-thalassemia trait: 2 alpha-globin genes mutated => mild microcytic anemia

Hemoglobin H disease: 3 alpha-globin genes mutated => bone marrow transplant/transfusions

Hemoglobin barts: 4 alpha-globin => intrauterine death

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

Sub-types of beta-Thalessemia?

A

Beta-Thalessemia train/minor

Beta-Thalessemia major and intermedia: 2 beta-globin genes mutated => major requires chronic blood transfusions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Treatment of thalessemia?

A

Complete bone marrow transplantation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Iron deficiency anemia is? Two causes he thinks matter?

A

Inadequate iron supply to sustain erythropoiesis

Causes: lack of iron in diet, inability to absorb iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Difference between Myoglobin and Hemoglobin?

A

Mgb:
Single polypeptide chain containing 8 alpha helices, coiled => binds 1 O2 (released by Hgb)

Hgb:
is tetrameric/made of 2 subunit types:
2 alpha and 2 beta chains = 2 alpha beta protomers
4 Heme groups (4 protoporphyrin rings)=> binds up to 4 O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Chemical orientations of heme due to O2 binding?

A

Unstable:
Deoxygenated Hgb - tense state (angled) => low affinity for O2 => more likely to transfer O2 to tissues

Stable:
Oxygenated Hgb - relaxed state (planar) => high affinity for O2 => recruit O2 in lungs (15 degrees rotational change)

Difference by 100 fold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Binding/coordination sites of Fe(2+) in heme?

A

Total of 6 binding sites:
1-4 => protoporphyrin ring along its plane
5 => proximal histidine

6 => O2 binding site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Oxygen - Hgb dissociation curve type?

A

Sigmoidal O2 dissociation curve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which conditions cause the sigmoidal curve to shift to the left?

A

Stabilization of R state => favor O2 binding

32
Q

Which changes lead the sigmoidal curve to shift to the right?

A

Stabilization of T state will favor O2 loss

33
Q

Why is O2 a positive allosteric effector?

A

Bc the ligand affinity of Hgb is increased by successive O2 binding

34
Q

Type of relationship between O2 and Hgb?

A

Positive cooperativity

35
Q

Function of negative allosteric regulators? Name them

A

=> drive the release of O2 in tissues => shift curve to right => help Hgb unload O2 => reduced O2 binding/affinity of O2 => T state > R state

Increased Temp/CO2
Decreased pH
2,3-BPG (Citric Acid Cycle)

36
Q

What is the Bohr Effect?

A

Contribution of H+/CO2 and therefore Hgb in acid-base regulation

Acidic = low pH => right shift
=> decrease in O2 affinity => response to low blood pH => resulting from increased CO2 concentration in blood

37
Q

Which enzyme catalyzes the buffer reaction between H2O + CO2 H2CO3 H + HCO3

A

Carbonic anhydrase (between CO2 and H2CO3)

38
Q

How is the T state stabilized?

A

3 factors:

H+ => pH
CO2/HCO3-
Increased temp

39
Q

What is altitude sickness?

A

Leads to hypoxia => headache/nausea/ life threatening pulmonary/cerebral edema => death

Treat: enzyme inhibitor causing alkaline blood

40
Q

Difference between fetal and normal Hbg?

A

Fetus has to extract O2 from mothers RBC

Uses different set of globin genes as part of Hgb

Adult uses HgbA, fetus uses 2 alpha+2 gamma chains = HgbF

41
Q

What is the immediate response to Hypoxia?

A

Cells must turn to anaerobic respiration => lactic acid => lower pH (=>shifts O2 curve to right/favors T state/releases more O2)

42
Q

What is the 24h response to hypoxia?

A

RBCs increase 2,3BPG => lowers O2 affinity of Hgb (right shift/increased O2 delivery to tissues)

43
Q

What is the days-4weeks response of hypoxia?

A

Goal: create more RBCs by secreting erythropoietin (Epo):

Kidney cells = high O2 demand = sensors of O2 delivery

Low O2 to kidney cells => hypoxia-inducible factor (transcription factor) not degraded => turns on multiple genes => incl. gene to secrete Epo

Epo migrates to bone marrow => binds to Epo receptor => activates JAK and STAT (signal transducer and activator of transcription) => blocks RBC apoptosis => increase hematocrit => increase O2 carrying capacity

44
Q

Type of gene mutation of sickle cell disease?

A

Recessive point mutation in beta-globin gene

=> mutation results in substitution of neg charged glutamic acid with hydrophobic valine at AA in pos #6 => early mortality

=> hydrophobic = sticky patch

45
Q

Treatment of SCA and hydroxyurea?

A

Use of hydroxyurea => increase expression of gamma-globin => can replace beta-globin in Hgb

46
Q

Functions of iron?

A

Oxygen carrier: 2/3 of 4g in Hgb

Immediate oxygen storage: myoglobin in muscle

Energy production: cofactor (cytochromes of oxidative phosphorylation)

Detoxification => cytochrome p450 enzymes

Immune protection

47
Q

Fe3+ ?

A

Ferric

48
Q

During iron transport in the GI, what reaction happens in the intestinal lumen?

A

Fe(3+) –ferric reductase–> Fe(2+)

49
Q

What happens with iron in the enterocyte cell?

A

Fe(2+) uses DMTI (divalent metal transporter to enter cell) –>
blood through ferroportin –>
Fe(2+) => converted back to Fe(3+) =>
bound to transferrin => carried

50
Q

After iron is taken up by the intestines (1-2mg/day), transferrin transports iron to?

A

75% bone marrow for red blood cell production

10-20% storage via ferritin in liver/heart

5-15% other

51
Q

What is the most abundant protein for iron storage (cytosolic protein)? Stored in what type of cells?

A

Ferritin in reticuloendothelial cells

=> 24 unit multimer of heavy/light chains => hollow shell

=> plasma ferritin = indirect marker for amount of iron stored

52
Q

Excess iron leads to? Treatment?

A

Damaging O2 free radicals => toxic to heart/liver mostly

Treat: iron chelator => deferoxamine/deferasirox => binds free iron in blood = iron-chelator complex

53
Q

Function of hepcidin?

A

Body’s way of regulating uptake/availability of iron

High iron stores => hepcidin high for example as a result of inflammation (IL-6)

=> negative regulator of ferroportin = blocks ability of cells to secrete iron into blood:

Enterocytes: decreased iron absorption
Reticuloendothelial cells: decreased ability of iron to be mobilized

54
Q

Diagnosis of iron deficiency anemia?

A 
Diagnosis: 
Microcytic anemia (smaller/pale RBCs) => poor Hgb production

Low ferritin (ferritin increases in times of stress/illness)

Low transferrin saturation (~10% iron compared to normal 30-40%)

55
Q

Treatment of iron deficiency anemia?

A

Provide dietary iron
=> red meat, oral elemental iron+OJ/Vit C (helps reduce iron for DMTI)

Can be due to excessive milk consumption =>inflammation=>poor absorption => give elemental iron+decrease milk consumption

Intravenously

Supplemental iron

56
Q

Two phases of clotting?

A

Platelet plug formation:
Temporary repair until a proper clot can form

Clot formation:
Longer term, stronger, clot formation stops

57
Q

Steps of platelet plug formation?

A

Damage of endothelial lining => expose collagen on basement membrane and von Willebrand Factor vWF

Adhesion => aggregation (fibrin linking of glycoprotein Gp IIb/IIIa receptors)=> activation (adhesion=> degranulate =>ADP,TXA2)

58
Q

Drug that inhibits platelet plug formation/aggregation?

A

Nonsteroidal anti-inflammatory drugs NSAIDs act by inactivating/inhibiting cyclooxygenase COX => inhibit resultant prostaglandins/prostacyclins/thrombaxans

=> Aspirin noncompetitively/irreversible inhibits COX enzyme (acetylation)

=> Ibu is reversible

59
Q

Two pathways of clotting cascade and their relationship? Combine where?

A

Intrinsic pathway (Factor 8,9,11,12 activated by Ca, triggered by 12)
Extrinsic pathway (triggered by Factor 7, tissue Factor 3)
Both triggered by injury duuhh
=> independent

Combined efforts lead to common pathway

60
Q

Steps leading up to common pathway and committing step in the clotting cascade?

A

Factor X is cleaved into Xa

Committing step: Factor Xa/Ca/V => convert prothrombin into thrombin

Fibrinogen –thrombin–> fibrin

61
Q

Factor X in the clotting cascade is activated how?

A

Intrinsic/extrinsic activated factors, Ca, PL

62
Q

Fibrinogen’s monomer is?

A

Fibrin

=> mesh ensnare RBCs

63
Q

Function of thrombin?

A

Activation of fibrin

Thrombin cleaves FPA and FPB domains to convert fibrinogen to fibrin and fibrinopeptides => breaks Arg-Gly bond

64
Q

Fibrin aggregation results in? Steps sorta?

A

Forms a soft clot

Fibrinogen –thrombin–>Fibrin monomer (FPA/FPB) => fibrin dimer => fibrin polymer

65
Q

What causes the soft clot to turn into a hard clot?

A 
Factor XIII cross linking: 
Factor XIIIa (enzyme) stabilizes soft clot=>hard clot
66
Q

Characteristics of hemophilia? Treatment?

A

Group of diseases characterized by frequent hemorrhages (spontaneous/traumatic)

  • Hemophilia A => 80% of patients => Factor VIII deficiency
  • Hemophilia B => 20% of patients => Factor IX deficiency

=> both intrinsic pathway factors
=> intravenous factors fix it

67
Q

Characteristics of von Willebrand’s disease vWD?

A
  • mild, most common bleeding disorder due to vWF deficiency

=> vWF => platelet adhesion/Factor VIII survival

68
Q

3 major regulators that serve to control clot formation?

A

Anti-Thrombin III (ATIII)
Protein C
Protein S
=> hypercoagulable state

69
Q

function of protein C/S?

A

Protein C + Protein S => degrade/inactivate Factors Va and VIIIa

Protein C (MEMBRANE BOUND COMPLEX)–thrombin etc–>activated protein C + Protein S

70
Q

Protein C/S and Thrombomodulin/thrombin lead to?

A

Lyses of fibrin

71
Q

What vitamin contributes to clotting and it’s deficiency hinders clot formation and causes chronic bleeding?

A

Vit. K

Can be deficient due to antibiotic damage to gut flora

72
Q

How do plasminogen activators contribute to plasmin and clot dissolution?

A

They break plasminogen between arginine 560 and valine 561 (SS bond) => further cleavage produces angiostatin

73
Q

Function of angiostatin?

A

Limits new growth of blood vessels

74
Q

Which condition is attempted to diagnose by measuring the level of D-dimers?

A

Deep Vein Thrombosis DVT or pulmonary embolism

=> confirm and grade extent of existing clot

75
Q

3 enzymes/factors increasing plasminogen dissolution (clot dissolution)?

A

Tissue type plasminogen activator
Streptokinase
Urokinase-type plasminogen activator

Plasminogen –> plasmin

76
Q

Characteristics of Factor V Leiden Polymorphism?

A

=> changes Arg->Glutamine in Factor V clotting factor

Thats where protein C acts => protein C less efficient in regulating Factor V => higher levels of Factor Va

=> excessive thrombin production, fibrinogen activations, clot formation

=> hypercoagulable state => causes DVT => pulmonary embolism etc

BioChem Exam 3 (5 decks)

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