88
]. N. R. GRAINGER
growth of cells in these experiments. Oxygen consumption of the same yeast
suspension was measured with a Warburg apparatus. Nitrogen was estimated
using Kjeldahl's method followed by steam distillation of aliquots of the neutralised diluted digest into boric acid which was then backtitrated with 0.01 N. HCl
using mixed indicator. The same methods were used with the other organisms.
With Nucella the suspension medium was sea water. Tap water which had been
passed through activated charcoal was used for the remaining organisms.
The bridge was balanced by altering the variable resistance D (Fig. 1) until the
galvanometer H showed no deflection. The reading of D was then noted. Readings
were taken every five minutes for a period of at least 1 hr (after an initial equilibriation period of 1-2 hrs). Oxygen was slowly bubbled through the flask
for 1/2 min every 5 min but in some of the yeast experiments bubbling was continuous. Tests showed that adequate oxygen was present throughout each experiment. In most experiments the flask contents were slowly stirred by a magnetic
stirrer.
Results: The results are summarised in the Table. Also included are
some of the findings of other authors. These have . . been recalculated to
convert them to the same units as are used in the present work. The dog
data is that obtained by LUSK as quoted in [2]. At the bottom of the Table
are the calculated oxygen/heat equivalences for four substances. The
values for these are based on their complete oxidation. The LIB values
were taken from [1]. In the case of alanine and glutamic acid the oxidation
Relation between heat production and O 2 consumption
O 2
Heat
No.
conEquivalent
Temp.
proof
of
sumpduction
Exps.
DC
tion
cal/mg N/
1 ml02
pl/mg N/
(calories)
hr
hr
Bakers yeast
9
20.4
1170
5.76
4.92
Bakers yeast
5
25.8
2305
6.16
2.67
Bakers yeast
5
30.0
2435
9.47
3.89
Bakers yeast
6
34.9
3359
12.12
3.61
Lumbriculus sp.
2
20.4
22.1
0.25
11.26
Asellus aquaticus
2
20.4
27.5
0.12
4.47
Nucella lapillus
1
20.4
16.8
0.08
4.69
Limnaea pereger
1
20.4
20.3
0.05
2.60
Rana temporaria tadpoles
1
20.4
43.2
0.30
6.95
Bird erythrocytes (5)
4.3-5.0
Vibrio metschnikoff (5)
5.6-6.4
Strongylocentrous larvae (4)
3.9
Dog (2)
4.85
Glucose
5.01
Palmitic acid
4.65
Alanine
4.61
Glutamic acid
5.21
]. N. R. GRAINGER
growth of cells in these experiments. Oxygen consumption of the same yeast
suspension was measured with a Warburg apparatus. Nitrogen was estimated
using Kjeldahl's method followed by steam distillation of aliquots of the neutralised diluted digest into boric acid which was then backtitrated with 0.01 N. HCl
using mixed indicator. The same methods were used with the other organisms.
With Nucella the suspension medium was sea water. Tap water which had been
passed through activated charcoal was used for the remaining organisms.
The bridge was balanced by altering the variable resistance D (Fig. 1) until the
galvanometer H showed no deflection. The reading of D was then noted. Readings
were taken every five minutes for a period of at least 1 hr (after an initial equilibriation period of 1-2 hrs). Oxygen was slowly bubbled through the flask
for 1/2 min every 5 min but in some of the yeast experiments bubbling was continuous. Tests showed that adequate oxygen was present throughout each experiment. In most experiments the flask contents were slowly stirred by a magnetic
stirrer.
Results: The results are summarised in the Table. Also included are
some of the findings of other authors. These have . . been recalculated to
convert them to the same units as are used in the present work. The dog
data is that obtained by LUSK as quoted in [2]. At the bottom of the Table
are the calculated oxygen/heat equivalences for four substances. The
values for these are based on their complete oxidation. The LIB values
were taken from [1]. In the case of alanine and glutamic acid the oxidation
Relation between heat production and O 2 consumption
O 2
Heat
No.
conEquivalent
Temp.
proof
of
sumpduction
Exps.
DC
tion
cal/mg N/
1 ml02
pl/mg N/
(calories)
hr
hr
Bakers yeast
9
20.4
1170
5.76
4.92
Bakers yeast
5
25.8
2305
6.16
2.67
Bakers yeast
5
30.0
2435
9.47
3.89
Bakers yeast
6
34.9
3359
12.12
3.61
Lumbriculus sp.
2
20.4
22.1
0.25
11.26
Asellus aquaticus
2
20.4
27.5
0.12
4.47
Nucella lapillus
1
20.4
16.8
0.08
4.69
Limnaea pereger
1
20.4
20.3
0.05
2.60
Rana temporaria tadpoles
1
20.4
43.2
0.30
6.95
Bird erythrocytes (5)
4.3-5.0
Vibrio metschnikoff (5)
5.6-6.4
Strongylocentrous larvae (4)
3.9
Dog (2)
4.85
Glucose
5.01
Palmitic acid
4.65
Alanine
4.61
Glutamic acid
5.21