Homeostasis and Feedback Systems: Temperature Regulation in Humans

This report explores the intricate mechanisms of human temperature regulation, focusing on the principles of homeostasis and feedback systems. The report details how the human body maintains its internal temperature in response to external environmental changes. It highlights the role of thermoreceptors, the hypothalamus as the control center, and effectors such as blood vessels and skeletal muscles. The report specifically addresses the body's response to decreased temperatures, including the process of shivering and vasoconstriction. This is a negative feedback system, where the body responds to a stimulus (decreased temperature) to restore the internal balance. The report also cites various sources, including journals and books, to support the information provided. The report discusses the physiological processes involved in maintaining body temperature, providing a comprehensive overview of the subject.

Bioscience 1

TABLE OF CONTENTS
part A...............................................................................................................................................3
1) Feedback system for decreased external temperature.............................................................3
References........................................................................................................................................4
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PART A
1) Feedback system for decreased external temperature
Homeostasis is a balance position for the body which is attained for coordinating with the
changes that take place in the external environment. Both the internal body conditions and
external environment is continuously changing. The normal body temperature is 36º C. If the
external surroundings have elevated temperatures then human body starts sweating while in case
of decreased atmospheric temperatures, the body starts shivering. The changing temperature is a
stimuli and body reactions like sweating and shivering are responses to this stimuli (Modell & et.
al., 2015). Hence, an internal feedback mechanism is initiated for responding to different types of
stimulus.
There are three main components of a complete feedback system. These include
receptors, control centre and effectors. The human body has sensors which detect the changes or
stimulus which are addressed by body (Rowland, Bal & Periasamy, 2015). These sensors are
known as receptors. In case of decreased temperature level of surroundings, the receptors are
thermoreceptors in the skin. They detect that there is a decrease in external temperature as
compared to the internal body. The response to stimulus is given by control centre.
Hypothalamus is the control centre in this feedback system. It is a small portion of the brain
which consists of small nuclei and a variety of functions (Nijhout, Best & Reed, 2014). The
signal of shivering is initiated from the hypothalamus to the effectors. Blood vessels and the
skeletal muscles are two significant effectors for this feedback system.
Effectors are activated and the message signal that is received from brain is interpreted as
shivering actions of the body. Blood vessels undergo vasoconstrict which means the diameter of
the blood vessel is decreased and the blood flow in the particular area of skin which is subjected
to decreased temperatures is reduced. This changes the normal skin colour to pale surface.
Skeletal muscles perform rapid contractions. This movement leads to generation of heat and
warmth in the body which is trapped by the surface that is pale due to decreased blood flow. The
rapid contractions is seen in the form of shivering by the body (Rowland, Bal & Periasamy,
2015).
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The type of feedback system which has been described above is a negative feedback
because there was an imbalance in the normal body state. Homeostatic controls are generally
negative because they are activated as a response to stop the effect of stimulus on the body.
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REFERENCES
Books and Journals
Modell, H. & et. al. (2015). A physiologist's view of homeostasis. Advances in physiology
education. 39(4). 259-266.
Nijhout, H. F., Best, J., & Reed, M. C. (2014). Escape from homeostasis. Mathematical
biosciences. 257. 104-110.
Rowland, L. A., Bal, N. C., & Periasamy, M. (2015). The role of skeletal‐muscle‐based
thermogenic mechanisms in vertebrate endothermy. Biological Reviews. 90(4). 1279-1297.
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