Page 71 - The Cell in 40 Topics

s you'll know, the normal body temperature for all human
beings is between 36.5 to 37 degrees Celsius, or 96 to 98.6
degrees Fahrenheit. But have you ever wondered about the
source of your body temperature and what maintains it at that constant
level?
Central heating systems are generally employed to keep our homes
warm, with thermostats that regulate the temperature. The householder
warms his home by turning the thermostat up to the desired level. But
what exactly is the human body's central heating system? And how is that
"thermostat" adjusted?
The source of body heat is the 100 or so trillion cells in the human
body. During the course of their activities, the cells emit a certain amount of
heat, which causes the body to warm up. But it is the hormone thyroxin, a
tiny molecule that regulates—with God's inspiration—how much heat
each of these micro-heaters should give off. In other words, thyroxin acts as
a thermostat (Figure 56).
The way a cell generates a specific level of heat as it operates, and that
the total amount emitted by those roughly 100 trillion cells reaches the

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