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People are mammals, and mammals are warm-blooded creatures, capable of maintaining a relatively constant internal temperature regardless of the environmental temperature. Body temperature control is one example of homeostasis—an organism’s self-regulating process that tends to maintain internal stability while adjusting to conditions in ways that are optimal for survival. The optimal temperature of the human body is 37 °C (98.6 °F), but various factors can affect this value, including exposure to the elements in the environment, hormones, an individual’s metabolism, and disease, which can lead to excessively high or low body temperatures. Body temperature is regulated mainly by the hypothalamus in the brain. Feedback about body temperature is carried through the nervous system and circulatory system (whose pressure-sensitive receptors in the blood vessels work with the nervous system to collect and communicate information on blood pressure) to the brain, where the breathing rate, blood sugar levels, and metabolic rate are adjusted to compensate for temperature changes. Heat loss is promoted by reduction of muscular activity, by perspiration, and by heat-exchange mechanisms that allow blood to circulate near the skin surface. Heat loss is reduced by the body’s insulation mechanisms, including reduction of blood flow to the skin and the fat beneath the skin, and by use of clothing, shelter, and external heat sources. In addition, the body can generate heat through shivering, a response regulated by the hypothalamus. The range between high and low body temperatures constitutes the homeostatic plateau—the "normal" range that sustains life. As either of the two extremes is approached, corrective action (through negative feedback) returns the system to the normal range. A version of this answer was originally published on Britannica’s Beyond. 1) Thyroid hormone levels drop below normal range. Sensory neurons respond by sending nerve impulses to neurosecretory cells in the hypothalamus. 2)Neurosecretory cells secret thyrotropin-releasing hormone (TSH) into the blood, which carries it to the anterior pituitary 3) TRH causes anterior pituitary to secrete thyroid stimulating hormone (TSH) into the circulatory system. 4)TSH stimulates endocrine cells in the thyroid gland to secrete thyroid hormone (T3 and T4) into the circulatory system. 5) Thyroid hormone levels increase in the blood and body tissues. Thyroid hormone acts on target cells throughout the body to control bioenergetics; help maintain normal BP, HR, and muscle tone; and regulate digestive and reproductive functions. 6)As levels return to the normal range, thyroid hormone blocks TRH release from the hypothalamus and TSH release from the anterior pituitary forming a negative-feedback loop that prevents overproduction of thyroid hormone.
Why do we need to maintain a constant internal environment? - OCR 21COrganisms can only function if their internal conditions are kept within a specific range. This is called homeostasis. The endocrine system secretes hormones for homeostasis to occur.
Body temperature must be controlled within a very narrow range so that the body can function properly. In particular, enzymes in a body's cells must have the correct temperature to be able to catalyse chemical reactions. Extremes of body temperature are dangerous: Temperature control is the process of keeping the body at a constant core body temperature close to 37°C. The body can only stay at a constant temperature if the heat generated is balanced and equal to the heat lost. Although the core temperature must be close to 37°C, fingers and toes can be colder. This is because energy is transferred from the blood as it travels to the fingers and toes. Responding to changes in temperatureIf the body becomes too hot or too cold, various mechanisms in the skin can be turned on or off. Too cold
Too hot
Skin responses
Capillaries do not move up and down inside the skin. Temperature is regulated by controlling the amount of blood which flows through the capillaries by changing the size of the blood vessels that supply them with blood. Muscle responsesMuscles can also receive messages from the brain when the body temperature decreases. They respond by shivering. Shivering causes the muscles to contract and relax quickly. This process generates heat. Experiments to investigate temperature changeThe processes by which organisms regulate their body temperature can be modelled using regular lab equipment. A beaker contains warm water at a temperature of 40°C. This represents an organism with a body temperature of 40°C. There are two methods you can use to model two ways the organism can control its body temperature. Method 1 - Using a single Bunsen burner to maintain a constant temperature. When the temperature falls below 40°C, the Bunsen burner is used to heat the water back up. This represents using a single effector to control body temperature. Method 2 - Using a Bunsen burner and ice to maintain a constant temperature. When the temperature falls below 40°C, the Bunsen burner is used to heat the water back up. If the temperature rises above 40°C, ice is added to the beaker of water to bring the temperature back down. This method has two ways of controlling temperature, which work oppositely. It represents using effectors antagonistically to control body temperature. QuestionWhich method models what happens in the human body? Method 2. It models how different mechanisms in the skin are used to increase or decrease body temperature.
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Why is it important to keep your body temperature at 37 degrees?It is important that we maintain an optimum temperature for the enzymes in our body (around 37 degrees celsius). If it's too hot, our enzymes will denature and will become inactive/lose their function. If it's too cold, the enzymes will too become ineffective (their function will slow down too much).
Why is our body temperature maintained at a constant 98.6 F?Our internal body temperature is regulated by a part of our brain called the hypothalamus. The hypothalamus checks our current temperature and compares it with the normal temperature of about 37°C. If our temperature is too low, the hypothalamus makes sure that the body generates and maintains heat.
Why does the body need to be at 98.6 degrees?Scientists have found the reason why our body temperature is 98.6° Fahrenheit (37°C). Apparently it's the perfect balance, as it's warm enough to prevent fungal infection but not so hot that we need to eat nonstop to maintain our metabolism.
Why is it important for your body to maintain a stable internal temperature?In particular, enzymes in a body's cells must have the correct temperature to be able to catalyse chemical reactions. Extremes of body temperature are dangerous: high temperatures can cause dehydration, heat stroke and death if untreated. low temperatures can cause hypothermia and death if untreated.
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Why do you need to maintain a stable internal temperature of 98.6 degrees Fahrenheit about 37 degrees Celsius )?
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