問題一覧
1
What percentage of the cytoplasmic content of red blood cells (RBCs) is made up of hemoglobin?
95%
2
How is free hemoglobin in the plasma managed by the body?
It is salvaged to preserve iron and amino acids
3
What is hemoglobin’s main function in the body?
To transport oxygen and carbon dioxide
4
At what concentration is hemoglobin found within red blood cells (RBCs)?
34 g/dL
5
What is the molecular weight of hemoglobin?
64,000 Daltons
6
Hemoglobin helps maintain acid-base balance by:
Binding and releasing hydrogen ions
7
What does hemoglobin transport, apart from oxygen and carbon dioxide?
Nitric oxide
8
Which method was first used to describe the structure of hemoglobin?
X-ray crystallography
9
What type of protein is hemoglobin?
Globular protein
10
How many polypeptide chains make up the hemoglobin molecule?
Two different pairs
11
How many heme groups are present in a hemoglobin molecule?
Four
12
Where are the heme groups located in the hemoglobin molecule?
Imbedded in the four polypeptide chains
13
What type of iron is found in the center of the heme group?
Ferrous iron (Fe²⁺)
14
Heme consist of a ring of carbon, hydrogen, and nitrogen atoms called?
Protoporphyrin IX
15
Where is each heme group positioned within the hemoglobin molecule?
In a pocket of the polypeptide chain near the surface
16
How many oxygen molecule is bined with the ferrous iron in each heme group?
one oxygen molecule
17
What happens when ferrous iron (Fe²⁺) is oxidized to ferric iron (Fe³⁺)?
Hemoglobin can no longer bind oxygen
18
What is oxidized hemoglobin called?
Methemoglobin
19
Which hemoglobin chain is represented by the symbol α?
Alpha
20
Which hemoglobin chain is represented by the symbol β?
Beta
21
Which hemoglobin chain is represented by the symbol γA?
Gamma A
22
Which hemoglobin chain is represented by the symbol γB?
Gamma B
23
Which hemoglobin chain is represented by the symbol δ?
Delta
24
Which hemoglobin chain is represented by the symbol ε?
Epsilon
25
Which hemoglobin chain is represented by the symbol ζ?
Zeta
26
Which hemoglobin chain is represented by the symbol θ?
Theta
27
This globin chains consist of 141 amino acids?
Alpha and Zeta
28
This globin chains consist of 146 amino acids?
Beta, Gamma A, Gamma G, Delta, Episilon
29
In the YA (Gamma A) hemoglobin chain, which amino acid is found in position 136?
Alanine
30
Which amino acid occupies position 136 in the YG (Gamma G) hemoglobin chain?
Glycine
31
Which hemoglobin chain has an unknown number of amino acids?
Theta (θ)
32
How many globin chains make up a hemoglobin molecule?
Two pairs of identical chains
33
How many amino acids are there in each globin chain?
141 to 146
34
What gives rise to different types of globin chains?
Variations in amino acid sequences
35
Each globin chain is divided into how many helices?
Eight helice
36
The helices is separated by?
Seven nonhelical segments
37
What designations are given to the helices in the globin chain?
A to H
38
What is the sequence between the N-terminus and the A helix called?
NA
39
What segment connects the A and B helices in the globin chain?
AB
40
Which segment connects the H helix to the C-terminus?
HC
41
What does the primary structure of hemoglobin refer to?
The amino acid sequence of the polypeptide chains
42
What does the secondary structure of hemoglobin describe?
The arrangement of helices and nonhelices
43
What is the tertiary structure of hemoglobin?
The pretzel-like arrangement of helices
44
Quaternary structure is also called?
Tetramer
45
What does the quaternary structure of hemoglobin refer to?
Complete hemoglobin molecule