Question

How does the human body generate heat.

Answer 1

Hint: In the human body, every cell produces heat as the energy is burnt up. However, some organs will be more than the other organs like the brain or muscles.

Complete solution:
The major sources of heat are metabolism and muscle heat apart from the other minor sources.
In Metabolism, the heat is released in the form of chemical reactions and also in the form of cellular respiration. The liver is the major source of metabolic heat. The other source is the brain that uses 20% of the glucose processed in the human body. The other organs release the heat when they are acting like the intestine when it is digesting and moving the nutrients into the circulation process.
The muscles will release the heat with every contraction and hence the constant source of the heat is constantly beating the heart. Also, a lot of heat is produced by the skeletal muscles during intense physical activity.
Also, a lot of heat is generated by the constant physiological activities. The friction of blood against the blood vessel walls produces heat. There is always some heat that is released in every movement and that is not random.
Depending on the situation, the heat production may vary. The more or less constant would be the heart, the liver and the brain. The heat produced by the intracellular activity is also more or less constant, as these cells have to perform routine things.

Note: In some special situations also heat is generated in the human body like a fever. During the fiver, a lot of heat is produced as the heat is generally associated with the increased heartbeat rate and with faster breathing, etc.