Brainscape's Knowledge GenomeTM

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


See full index

Biochem > Lecture 8 & 10 Hemoglobin > Flashcards

Lecture 8 & 10 Hemoglobin Flashcards

1
Q

Erythropoeisis

A

Formation of RBCs
Starts at pluripotent stem cell ends at 2^11
Only other time you have proliferation like this is with Cancer

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

Erythrocytes

A 
No nucleus, no DNA and no regeneration
120 day lifespan
Use glycolysis
B12 and Folic acid are main builders
Biconcave shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Free iron

A

Toxic
Most common type of childhood poison
Transitional metal 2+ or 3+

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

RBC ruptures

A

Releases Hgb into the cell

3 serum proteins to clean it up -haptoglobin, transferrin

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

Hemoglobin is a

A

Tetramer

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

Hemoglobin is a tetramer

A

Has quaternary structure that provides stability and regulation
Each has a heme - a porphyrin ring with iron
Behaves like a dimer of dimers - interact with each other

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

Globin chain made of

A

Eight alpha-helices

a, b, c, d, e, f, g, h

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

2 Alpha like chains

A
  1. Zeta

2. Alpha

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

4 Beta like chains

A
  1. Epsilon - embryonic
  2. Gamma - fetal
  3. Delta - tiny bit of this
  4. Beta - adult, 1 week after birth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Embryonic Hgb

A

Epsilon

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

Fetal Hgb

A

Gamma

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

Small amount of this type Hgb

A

Delta

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

Adult Beta like chain

A

Beta

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

Leghemoglobin

A

1st branch of Hgb tree

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

Myoglobin

A

2nd branch of Hgb tree

Chromosome 22

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

Hemoglobin Alpha

A

3rd branch of Hgb tree

Chromosome 16

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

Hemoglobin Beta

A

Last branch of Hgb tree
Chromosome 11
Not sure evolutionary purpose

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

Typical patient has this type of Hgb

A

A2B2

19
Q

Hgb exists in

A

2 conformations
One is oxygenated
Alpha helix is dominant

20
Q

Porphyrin ring and Fe 2+

A

Heme group
4 per
Iron binds to oxygen

21
Q

2 parts of Heme

A

Porphyrin Ring

  • heterocyclic tetrapyrrole
  • planar and hydrophobic
  • bound to globin chain

One Fe 2+ per chain

  • 4 per tetrameric molecule
  • Oxygen binding
22
Q

Porphyrin Ring

A

Heterocyclic tetrapyrrole
Planar and hydrophobic
Bound to globin chain

23
Q

One Fe 2+ per

A

Chain

  • 4 per tetrameric molecule
  • oxygen binding
24
Q

Fe 3+ is

A

Met hemoglobin

25
Q

Histidines

A

Proximal and Distal

-around the heme iron

26
Q

Function of Hgb

A

Transport of O2

27
Q

Mechanism of O2 Binding

A
  • Fe 2+ : O2 binding site
  • Cooperativity - intrasubunit communication
  • Reversible binding
  • Allosteric control
28
Q

O2 binding site

A

Fe 2+

29
Q

Allosteric control

A

*occurs throughout biochemistry
Where something other than substrates can regulate how it binds
-3 molecules that bind to Hgb and change the conformation

30
Q

Sigmoidal curve shows the

A

Cooperativity

-steep part shows the cooperativity

31
Q

Cooperativity

A 
Multi-subunit protein
Subunits exist in 1 of 2 conformations
Conformational change in one subunit induces a conformational change in another
-many stable contact points
-some contact points change
32
Q

Conformational change in one subunit….

A

Induces a conformational change in another

33
Q

Structure of Myoglobin

A

Monomer - can’t have cooperativity because it is a monomer
One Globin chain
-different gene - still has exact same fold, so 3D structure is identical
One Heme- Fe2+

34
Q

Allosteric control

A

Regulation of O2 affinity
Effectors
-bind to distinct sites (NOT active site)
-induce conformational change
-inhibit O2 binding - so deoxygenated conformation

35
Q

Negative Allosteric Effectors - 3 things that cause this

A
  1. Bind to distinct sites (not active site)
  2. Induce conformational change
  3. Inhibit O2 binding - so deoxy conformation
36
Q

Negative Allosteric Effectors

A

Protons (low pH)
CO2
2,3-bisphosphoglycerate

37
Q

Negative Allosteric Effector Proton

A

Low pH
AKA H+
*slight acidification during burn of E (fuel)

38
Q

Negative Allosteric Effector CO2

A

Ex. fire, byproduct is CO2, same as burning sugar or fat in mitochondria, CO2 is released

39
Q

Negative Allosteric Effector BPG

A 
2,3-bisphosphoglycerate
In clinical called DPG
An intermediate in glycolysis
One step rxn, enzyme for that is found in RBC they make it
Make more in high altitudes
40
Q

R and T Forms of Hemoglobin

A

R - Deoxyhemoglobin

T - Ocyhemoglobin

41
Q

O2 curve for fetus

A

To the L
Fetal has higher affinity for O2 because fetus is not breathing, mother is
BPG in fetus is decreased so O2 is increased

42
Q

Fetal Hgb and BPG

A

BPG is decreased in fetus, so it increases oxygen, so it shifts it to the L
AA sequence is different

43
Q

Hb F

A

Fetal Hgb
2 alphas, 2 gammas
Behave differently that Hgb A (maternal)
AA sequence doesn’t allow to bind to BPG so they have higher affinity for O2

Biochem (12 decks)

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