Brainscape's Knowledge GenomeTM

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


See full index

Biochemistry - Block 1 > Lecture 4 Biochem > Flashcards

Lecture 4 Biochem Flashcards

1
Q

Hemoglobin has how many Heme groups?

A

4 Heme groups; Tetrameric.

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

What kind of structure is Hemoglobin?

A

Quartenary Structure

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

What is the FXN of Hemoglobin?

A

It’s a transport protein for O2.

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

Hemoglobin is dependent on what? Due to this what kind of curve does it display??

A

Hemoglobin is dependent on O2, thus it displays a sigmoidal curve.

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

Sigmoidal Curve is for what protein? What does this mean?

A

Hemoglobin. Great grabber of oxygen when oxygen concentration is HIGH and really good at releasing oxygen to tissues when oxygen concentration is LOW.

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

Hemoglobin has how many alpha and beta sub units?

A

2 Alpha subunits 2 Beta-hemoglobin subunits 4 Heme group

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

Hemoglobin has what cooperativity?

A

h>1 ; cooperative, sigmodial curve

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

Where is Hemoglobin found?

A

In the blood.

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

At HIGH oxygen levels, Hemoglobin’s affinity for oxygen is?

A

High.

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

At LOW oxygen levels, Hemoglobin’s affinity for oxygen is?

A

Low.

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

Kinetics for Hemoglobin binding. What does the first ligand cause for the next ligand?

A

The binding of the first ligand causes conformational change for the next ligand to bind easier.

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

Taut, what form of oxygen in?

A

Deoxygenated!

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

Relaxed, what form of oxygen in?

A

Oxygenated!

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

In the lungs, hemoglobin is bound to?

A

Lungs = High Con of O2 Thus, more hemoglobin bound to Oxygen.

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

In the tissues, hemoglobin is bound to?

A

Tissues= Low conc of O2. Thus, less hemoglobin bound to Oxygen.

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

The steps in conformational change in hemoglobin.

A

1)O2 binds 2)Pulls Fe up to fit into the plane 3)prox HIS is moved 4)Alpha helix is moved 5)Alters neighboring subunit conformation at alpha- beta interface 6)Neighbor now has increase affinity for oxygen

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

Myoglobin and Hemoglobin is made up of mostly

A

Alpha Helices Globular Protein

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

One heme groups has how many pyrrole rings? What is this called? What does it bind to?

A

4 Pyrrole rings, tetrapyrrole and binds to Fe within the same plane.

19
Q

Iron is a ___ and it can bind to how many ligands?

A

tetrahedral and can bind 6 ligands.

20
Q

One Heme Subunit has what attached to it?

A

Distal Histidine Is too far away cannot bind iron leaving the 6th position unbound for O2 Proximal Histidine Binds iron

21
Q

Myglobin has how many heme groups?

A

One heme group.

22
Q

What kind of structure does Myglobin have?

A

Tertiary Structure

23
Q

Where is myglobin found in the body? Fxn?

A

In tissues, as as stroage protein.

24
Q

Myglobin has what kind of curve ? Affinity for oxygen?

A

A hyperbolic cure, affinity for oxygen is always HIGH, regardless of O2 concentration.

25
Q

Myoglobin has what type of cooperativity?

A

h=1, non-cooperative. Each subunit has the same affinity for oxygen.

26
Q

Hill equation is used for? What is Myglobin and Hemoglobins?

A

Used to find degree of O2 binding to hemoglobin

Greater than one it indicates cooperativity h>1, hemoglobin

h=1, no cooperativity, myoglobin

27
Q

Bohr Effect determines?

A

Determines if Hemoglobin needs to release oxygen due to the pH and CO2 concentration in tissues.

28
Q

When Ph drops and CO2 concentration increase, what shift will the curve make?

A

A shift to the right, to decrease hemoglobins affinit for oxygen and allow it to be released more easily.

29
Q

2,3 BPG has what effect on the Bohr curve?

A

Stabilizies the taut confirmation, and shifts the curve to the right.

30
Q

how many pyrrole rings does heme have?

A

4 pyrrole rings = tetrapyrrole.

31
Q

Within a alpha helix when the Ph drops

A

Taut (deoxy) hemoglobin conformation is favored when HIS is protonated.

Due to

When the ph drops, beta HIS becomes protonated and is stabilized by the negative of beta aspartate.

This maintains the (taut) deoxygenated confirmation

This decreases oxygens affinity

O2 is released

Stabilizes a critical salt bridge that tends to maintain hemoglobin in the deoxy T state

32
Q

Within an alpha helix when the CO2 is in high concentration

A

CO2 interacts with amino terminal of alpha subunits and that will create this carbamate that has a negative charge.

Then carbamate interacts with positively charged amino acids

Stabilizes the deoxygenated state

Releases O2

Salt links stabilize the T state of hemoglobin

33
Q

Everything about 2,3 Biphosphoglycerate

A

Negative allosteric effector

Floats around in our blood has a negative 5 charge to it

Going to interact with 3 positively charged groups on each Beta chain

2,3 BPG binds to hemoglobin by 2 Beta subunits.

Stabilizes the deoxyhemoglobin confirmation

Oxygen does not bind as tightly in blood due to 2,3 BPG.

Interacts with B chains

8 + charged group on B chains stabilize the 5 - charges on 2,3 BPG

34
Q

Hemoglobinopathies

A

Categories as most prominent changes to protein structure and fxn and regulation

35
Q

HbC (common)

A

Abnormal solubility, Mild Anemia.. Enlarged spleen.. Decrease RBC

36
Q

Hb titusivlle

A

Decrease O2 affinity, Mild Cyanosis

37
Q

HbM boston (Rare)

A

Ferric Heme ( fe 3+) instead of ferrous heme (fe 2+), Cyanosis of skin and mucous membranes.

38
Q

Kinetics for Hemoglobin

A

Tetrameric protein

Bind first ligand cause conformational change for the next ligand to bind easier

More ligands bound strength increases

39
Q

Which of the following is true about both myoglobin AND hemoglobin?

They are composed mostly of alpha helical proteins

They are both only found in the tissues

They both have sigmoidal curves

They are both tetrameric proteins

A

They are composed mostly of alpha helical proteins

40
Q

When 2,3-BPG is bound to hemoglobin:

The curve shifts to the left and oxygen affinity increases

The curve shifts to the right and oxygen affinity decreases

The curve shifts to the left and oxygen affinity decreases

The curve shifts to the right and oxygen affinity increases

A

The curve shifts to the right and oxygen affinity decreases

41
Q

Which of the following indicates that a protein shows cooperativity?

Hill coefficient = 0

Hill coefficient = 1

Hill coefficient = 2

Hill coefficient = 0.27

A

Hill coefficient = 2

42
Q

Which of the following is NOT true about myoglobin?

It has a hyperbolic curve

It binds oxygen on its heme group

It has a sigmoidal curve

It is a monomer

A

It has a sigmoidal curve

43
Q

All of the following directly interact with the iron in a heme group EXCEPT:

Proximal histidine

Porphyrin rings

Oxygen

Distal histidine

A

Distal histidine

Biochemistry - Block 1 (6 decks)

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