2.12-Hemo&MyoGlobin

Question 1

What is the Bohr effect?

Answer 1

Effects of CO2 and H+ on HemoGlobin

Question 2

Does cooperatively work in hemoglobin or myoglobin? Or both?

Answer 2

Hemoglobin only

Question 3

What type of oxygen binding curve does Hemoglobin have? What Partial Pressure does it bind at?

Answer 3

Sigmoidal. Binds at 26 torr

Question 4

What type of oxygen binding curve does Myoglobin have?

Answer 4

Hyperbolic

Question 5

What is the structure of hemoglobin? hint: how many dimers..etc

Answer 5

Its a TETRAMER composed of two Alpha-Beta Dimers

Question 6

What are the __3__ methods to get CO2 from the tissues to the lungs? Whats the major way?

Answer 6

Dissolved CO2 in blood, Carbamino-hemoglobin, and bicarb… Bicarb is MAJOR way, 14% Carbamate

Question 7

What 3 signalers facilitate the release of oxygen from hemoglobin?

Answer 7

Increase H+, Increased CO2, and Increased 2,3BPG…Think cell that is working hard needs more O2!!

Question 8

Which form of hemoglobin can be used to monitor long-term blood glucose control in diabetics?

Answer 8

Hemoglobin A1c

Question 9

What is the RATE LIMITING step in Heme Synthesis? What is the enzyme used? What Coenzyme is used?

Answer 9

Succunyl-CoA + Glyceine = DALA.. Enzyme:DALA Synthase COenzyme: Pyridoxal phosphate DALA DALA BILLS YO

Question 10

Where are the two main locations of Heme synthesis?

Answer 10

Bone marrow and liver

Question 11

What type of rings comprise the active sight of heme and myoglobin? Which ion form of iron is in the center?

Answer 11

4 Pyrrole (5C) rings; Fe2+

Question 12

What is myglobin made from? How many alpha helices? What keeps the O2 in?

Answer 12

One polypeptide chain and 8 alpha helices..A distal and a proximal histidine keep the oxygen in

Question 13

When does myoglobin have the highest affinity for oxygen? What Partial Pressure?

Answer 13

At LOW [O2] (2 torr). Its like a sponge for muscle cells

Question 14

What is the most common form of Hemoglobin in adults?

Answer 14

Hb A

Question 15

What type of hemoglobin has a higher affinity for O2 and therefore is genetically stimulated for sickle cell anemia pts?

Answer 15

Hb F (Fetal hemoglobin)

Question 16

Is hemoglobin considered hydrophilic or hydrophobic?

Answer 16

Hydrophobic, even though it has H bonds and ionic pairs!

Question 17

Which formation has a LOW affinity for O2? T or R?

Answer 17

Taut (release oxygen)

Question 18

Which formation has a HIGH affinity for O2? T or R?

Answer 18

Relaxed (pick up oxygen)

Question 19

What is the degree of difference between T and R?

Answer 19

15 degrees

Question 20

When oxygen binds to iron II does the active site go into the plane of the molecule or go out of the plane of the molecule?

Answer 20

It goes into the plane

Question 21

Why would high 2,3BPG increase hemoglobin release of oxygen? Which state does it put hemoglobin in? R or T?

Answer 21

2,3BPG is a byproduct of glycolysis. The cell is working hard and needs oxygen. T=taut=low O2 affinity=release of O2

Question 22

What about the structure of Fetal hemoglobin causes more O2 affinity? What about 2,3 BPG?

Answer 22

Because it has two alpha and two GAMMA subunits it does not bind 2,3 BPG as well. NO 2,3 BPG=NO T formation=Less release of O2

Question 23

How much of a pH difference causes an 11% difference in O2 release?

Answer 23

7.4 to 7.2 pH causes hemoglobin to release 11% more O2

Question 24

Does CO2 compete with O2 for binding sites on hemoglobin?

Answer 24

NO!

Question 25

What is the protein produced by RBCs that binds to alpha-chains on hemoglobin?

Answer 25

AlphaHemoglobinStabilizingProtein (AHSP)

Question 26

What is substituted for the normal glutamine on the Beta subunit for sickle cell anemia Pts? Does it affect deoxyhempglobin or oxyhemoglobin?

Answer 26

Valine causes mutancy, Affects deoxy but not oxy

Question 27

What do cells put out that will increase the affinity for more O2?

Answer 27

2,3 BPG

Question 28

Bohr effect?

Answer 28

effect of CO2 and Hydrogen Ions on O2 affinity