Hemoglobin Synthesis 1

Question 1

Structural defects of hgb is known as

Answer 1

Hemoglobinopathis

Question 2

Synthetic defects of hgb is also termed as

Answer 2

Thalassemias

Question 3

Most studied protein

Answer 3

Hemoglobin

Question 4

Why is hgb inside rbc

Answer 4

1. To prevent denaturation in the plasma
2. Prevent its loss through secretion in the kidney

Question 5

Amount of Hemoglobin in rbc

Answer 5

34 g/dL

Question 6

Cytoplasmic content of RBCs

Answer 6

Approx. 95%

Question 7

Molecular weight of hgb

Answer 7

64,000 Daltons

Question 8

Amount of hgb weight from that of the total body weight

Answer 8

1%

Question 9

Functions of hgb

Answer 9

1. Transports oxygen from lungs to tissues
2. Transports carbon dioxide from tissues to the
   lungs
3. Transports of nitric oxide
4. Contributes to acid-base balance

Question 10

A vasodilator substance associated with hgb

Answer 10

Nitric oxide

Question 11

How does hgb contribute to regulation of acid-base balance

Answer 11

There is a particular form of hgb that is considered as a stronger base and a stronger acid which allows it to either bind or release hydrogen ions, therefore making it able to balance or buffer the blood pH

Question 12

General compositions of hemoglobin

Answer 12

Hgb is composed of 2 different pairs of polypeptide chains (total of 4 polypeptide chains) with a heme group embedded to each (total of 4 heme groups)

Question 13

A heme group consists of:

Answer 13

1. Iron
2. Protoporphyrin IX
3. Other polypeptide chains
4. 2,3 BPG or 2,3 Bisphosphoglyceric acid

Question 14

A sometime resident / molecule in heme

Answer 14

2,3 Bisphosphoglyceric acid or 2,3 BPG

Question 15

Location pf 2,3 BPG on hgb

Answer 15

Center of hgb

Question 16

Why is 2,3 BPG a sometime / temporary resident

Answer 16

2,3 BPG is only present on low oxygen tension. Therefore, it is not present in the lungs (O2 is present here) but it is present / binds in tissues (low O2 tension) in order to facilitate release of oxygen to tissues.

Question 17

It is a ding of carbon, hydrogen, and nitrogen atoms

Answer 17

Protoporphyrin IX

Question 18

Type of iron present in hemoglobin

Answer 18

Ferrous iron (Fe2+) / iron in its reduced form

Question 19

Volume of 1 mol of oxygen

Answer 19

1.34 mL

Question 20

It consists of ferric iron / iron in its oxidized form

Answer 20

Methemoglobin

Question 21

Why is methemoglobin a dysfunctional hgb?

Answer 21

Once all 4 of heme groups are affected, it is no longer able to carry O2 which is its main function. However, if not all are affected, some are still capable of binding O2 but still, it’s no longer efficient with the oxygen-carrying capacity of the molecule

Question 22

Protein portion of the hgb

Answer 22

Globin

Question 23

Composition of globin

Answer 23

2 identical pairs of unlike polypeptide chains

Question 24

Variation in amino acid sequence gives rise to

Answer 24

Different types of globin chains

Question 25

What causes different types of hemoglobin

Answer 25

Variation in the combination of two globin chains

Question 26

8 helices of a globin chain is described as

Answer 26

Linear and rigid

Question 27

The 7 non-helical segments of a globin is described as

Answer 27

Flexible

Question 28

What are the different globin chains and their number of amino acids?

Answer 28

Alpha, beta, gamma, delta, epsilon, zeta Alpha and zeta have 141 amino acids ; beta, gamma, delta, and epsilon have 146 amino acids

Question 29

Describe the primary structure of hemoglobin

Answer 29

Amino acid sequence of polypeptide chains

Question 30

Describe the secondary structure of hgb

Answer 30

Chain arrangement in helices and non-helices

Question 31

Describe the tertiary structure of hgb

Answer 31

arrangement of the helices into pretzel- like configuration

Question 32

Where is heme located in the tertiary structure of hgb

Answer 32

Suspended between E & F helices

Question 33

It is described as the complete hemoglobin molecule

Answer 33

Quaternary structure / tetramer

Question 34

Purpose of the pretzel-like configuration

Answer 34

Globin chains are looped together in order to form cleft pocket to accommodate the heme

Question 35

Describe the amino acids inside and outside the cleft pocket

Answer 35

Inside: hydrophobic Outside: hydrophilic

Question 36

Purpose of the arrangement of amino acids inside and outside of the cleft pocket

Answer 36

1. This arrangement makes the hemoglobin water soluble 2. The arrangement maintains the iron in its reduced form (ferrous).

Question 37

non enzymatic binding of various sugars to the globin chain over the life span of the RBC

Answer 37

Glycation

Question 38

Normal amount of glycated hgb

Answer 38

4-6 percent

Question 39

Parameter used in the long term monitoring of DM patients

Answer 39

HbA1c / glycated hemoglobin

Question 40

Rbc stages where the production of hgb begins and ends

Answer 40

Basophilic normoblast to polychromatophilic erythrocyte

Question 41

Heme and globin synthesis each starts in what stage of rbc development

Answer 41

Pronormoblast

Question 42

Amount of hgb synthesized before nucleus exclusion

Answer 42

Approximately 65%

Question 43

Full hemoglobinization happens at what stage of rbc development

Answer 43

Polychromatophilic erythrocyte

Question 44

Location/s of hgb synthesis

Answer 44

Mitochondria and cytoplasm

Question 45

Where does globin synthesis start

Answer 45

Nucleus

Question 46

2 substances that initiates heme synthesis

Answer 46

Condensation of glycine and succinyl coenzyme A in the mitochondria

Question 47

Protein carrying iron that binds to the receptor of the developing rbc

Answer 47

Transferrin

Question 48

small amount of excess protoporphyrin in the mitochondrion is termed as

Answer 48

Free erythrocyte Protoporphyrin (FEP)

Question 49

FEP or ZPP significance

Answer 49

It serves as parameter in diagnosis of porphyria and stages of IDAs because its increase is a consequence of decrease or absence of iron