Blood collection tubes must be drawn in a specific order to avoid cross-contamination of additives between tubes. The recommended order of draw for plastic vacutainer tubes is: 1  First-blood culture bottle or tube (yellow or yellow-black top). 2  Second-coagulation tube (light blue top). 3  Third-non-additive tube (red top).
A thermocouple produces a voltage when the temperature of one of the contact points differs from the temperature of another, in a process known as the thermoelectric effect.he wires that make up the thermocouple must be insulated from each other everywhere, except at the sensing junction. Any additional electrical contact between the wires, or contact of a wire to other conductive objects, can modify the voltage and give a false reading of temperature.
Neurons in the hypothalamus are sensitive to changes in core temperature that could require a response from the body. Thermoreceptors are specialized neurons designed to be sensitive to changes in temperature.n the skin, thermoreceptors provide the brain with information about environmental temperature. This can be important, as it will alert the body to unusually cool or warm temperatures that might require an action, such as putting on a coat or shedding a layer of clothing to become more comfortable.