638
Bioinorganic Chemistry
Tab. 1
Essential elements in humans.
a
Element
pH 7 form
Serum conc.
Human amt.
Daily allowance
Na
Na
+
1
40mM
70g
1–2g
KK
+
4 mM
130 g
2–5 g
Mg
Mg
2
+
0.8 mM
22 g
0.3 g
Ca
Ca
2
+
2.4 mM
1,100 g
0.8 g
Mn
Mn
2
+
10 nM
12 mg
3 mg
Fe
Fe(OH)
3
17
µ
M
4 g
10–20 mg
Co
Co
2
+
2nM
1mg
3
µ
gv
it.B12
Cu
Cu
2
+
17
µ
M8
0
m
g
3
m
g
Zn
Zn
2
+
14
µ
M2
.
3
g
1
5
m
g
Cr
Cr(OH)
2
+
3nM
6mg
0
.
1mg
Mo
MoO
4
2
6nM
5mg
0
.
2mg
Cl
Cl
104 mM
80 g
2–4 g
PH
P
O
4
2
1.1 mM
600 g
1 g
SS
O
4
2
24 mM
120 g
0.7 g Met
b
Se
HSeO
3
1
µ
M5
m
g
0
.
1
m
g
FF
2
µ
M2
.
5
g2
m
g
II
0.4
µ
M
30 mg
0.15 mg
a
In addition to H, C, N, and O.
b
Essential amino acid methionine.
Tab. 2
Body fluids.
mM concentrations
Extracellular
Intracellular
Na
+
140
10
K
+
41
4
0
Ca
2
+
2
0.0001
Mg
2
+
11
Cl
104
4
HCO
3
27
10
HPO
4
2
&H
2
PO
4
11
0
SO
4
2
17
pH
7.4
6.6
important as an inorganic element but
only as part of the amino acids cysteine
and essential methionine. An additional
four elements, B, Si, V, and Ni, not
included in Table 1, are essential for other
organisms.
Table 2 shows the concentrations of sev-
eral ions in the blood plasma and in
a typical intracellular fluid. While the
concentration of Mg
2
+
is similar on both
sides of the cell membrane, the concen-
tration of K
+
is greater on the inside and
those of Na
+
and Ca
2
+
are greater on the
outside of a cell. A pump, driven by the pro-
tein Ca-ATPase, maintains the 20 000-fold
concentration difference for Ca
2
+
.These
concentration differences illustrate how
compartmentalization in biology leads
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