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Fever is a trait observed in warm and cold-blooded vertebrates that has been conserved for hundreds of millions of years (Evans, 2015). Elevated body temperature stimulates the body's immune response against infectious viruses and bacteria. It also makes the body less favorable as a host for replicating viruses and bacteria, which are temperature sensitive ...


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Short answer Birds emit infrared. Background Objects with a temperature higher than the background emit detectable infrared (IR). Endothermic (warmblooded) animals keep their body temperatures at around 37oC and given the relatively cool temperatures at the earth's surface, endotherms generally emit more IR than the background. Endothermic animals include ...


8

This due to a phenomenon called "cold shock". This induces a number of physiological changes in the fishs metabolism and also in its behaviour and can lead to death. The first paper cites some reasons in table 1: Brain and central nervous system response: Changes in neuronal activity Catecholamine and corticosteroid response: Release of hormones due to ...


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Factors that can lower body temperature: low environment temperature low metabolic rate hypothyroidism I couldn't find any relevant study addressing the Japanese people situation, but: There is significant variation in metabolic rate in humans, independent of differences in body size, body composition, age, and gender. Although it has been generally ...


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Short answer Water of 180 oF (82 oC) causes immediate scalding (thermal burn wounds). Background The severity of a scald injury depends on the temperature to which the skin is exposed, and for how long. Residential water heaters warm up tap water typically to 120 oF (48 oC). At this temperature, the skin of adults requires an average of five minutes of ...


8

Cooking is just a form of digestion. What is digestion? Digestion is the process of breaking down big molecules into smaller molecules. When you cook food you break down big molecules into its small components. Why do we digest food? Think about a long sequence of DNA for example. You eat corn and you have in your body a long sequence of corn DNA. ...


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Homeothermic multicellular organisms have special tissues that burn resources to warm up (usually this involves breaking the electron-transporting chain at the final stages of respiration to transform all chemical energy into thermal energy). And they have special tissues (fat) and enough body mass (this is more about the volume/area ratio) to keep this ...


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You constantly generate heat from metabolism. The ability of this heat to be transferred to your surroundings from your skin is tremendously different in air vs. water. This is known as thermal conductivity. The ability of water to remove heat from your skin is roughly 24 times that of air. See list of materials and their thermal conductivity rates here ...


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Fever normally under hypothalamic heat center's control which stays at limbic system of brain . Hypothalamus sets its own set point 36.4-37.2 in healthy peoples by some molecules named exogenous and endogenous pyrogens, especially PGE2 ,TNF and IL1. The most important mechanism for fever is directing blood flow from skin to deep vascular pools and ...


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Some 200 years ago Dr.Charles Blagden, then secretary of Royal Society of London, went into a room that had been heated to a temperature of 126 degree Celsius ( 260 Fahrenheit) , taking with him a few friends , a small dog in a basket and a steak.The entire group remained there for 45 minutes. Dr.Blegden and his friends emerged unaffected. This ...


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This is the modified answer in response to the discussion: Facts: There are warmth and cold receptors in the body at two places: The Peripheral receptors and the Central Receptors The peripheral receptors are present in skin and the central receptors in the body core at multiple sites the notable site being the hypothalamus The Temperature receptors have ...


5

Short answer Humans sense temperature differences. Background (Including edits based upon comments) Because the question is "Do humans perceive temperature or heat-flux?", I will answer the answer from a psychophysical perspective, i.e., by dealing with sensory awareness. Just as with many other sensory systems, temperature sensors in the human body ...


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As you can see on the diagram below, oxygen solubulity in water drops by increasing temperature, so your fish has to breath more to get the same amount of oxygen. ref You can find more info about why gas solubility is temperature dependent here: Chemistry (Averill & Eldredge) / Effects of Temperature and Pressure on Solubility.


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Flux is defined as amount of heat transferred per unit area per unit time. Our body does not perceive heat flux. It perceives temperature and tries to adjust heat exchange mechanisms until thermal homeostasis is achieved (in all warm blooded animals). This is a feedback controlled process. If it were to measure heat flux then the body cannot sense if it ...


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A very basic model of virus inactivation is exponential decay. You can describe exponential decay with the $N(t) = N_0e^{-\lambda t}$ equation, of if you want to use half-time, then with the $N(t) = N_02^{-t/t_{1/2}}$, where $N$ is the value which reduces by time, $t$ is the time, $\lambda$ is the exponential decay constant and $t_{1/2}$ is the half-life (...


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The discrepancy can be partly explained by where the temperature was measured from since the human body temperature ranges from 36.5 and 37.5 °C. For example it is 36.8 ± 0.4 °C when measured under the tongue (http://en.wikipedia.org/wiki/Human_body_temperature). Additionally The body temperature of a healthy person varies during the day by about 0.5 °C (0.9 ...


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Gains heat; humans are not particularly well-adapted to make use of heat as an energy source. In a simple matter, if something you eat is hot when it goes in then the average temperature of the body has increased. More relevantly (and to get this more on-topic for biology), eating anything will generally increase your body temperature, as in order to ...


4

In response to cold your body causes blood supply to the skin to drop in the whole body. This is to conserve heat, but results in us feeling really cold. Exercising reverses this, resulting in an increased blood supply to the skin in order to remove excess heat and in this case we feel hot. As mentioned, the head receives a large blood supply, and ...


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Comparing Biopython MetlingTemp to other calculators. I have written the recent version of MeltingTemp in Biopython's SeqUtils. I have extensively tested the Tm calculations against other programs like MELTING and Primer3Plus and other online Tm calculators with consistent results, thus I'm pretty confident that there is no gross error in the module. The ...


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This paper actually goes into the whole history of organ transplants. In short it seems to have the following effects: preservation - usually with a specific solution to help. slows down extracorporeal ischaemic damage slows down hypoxic damage slows down the metabolism (energy consumption) and thus the need for oxygen that blood provides. Remember that ...


4

Low temperatures change the speed of different chemical reactions, throwing delicately balanced systems out of balance. How resilient a creature is to temperature changes is largely a function of how complex it is, and how buffered it is against this kind of change. Tardigrades as kmm mentioned essentially can't be killed by cold, surviving down to almost ...


4

Dinosaurs is a very broad term which includes both the ancestors of birds as well as modern reptiles. But that analogy stretches as far to say that a bird is a modern dinosaur and a reptile is a modern dinosaur but a bird is not a reptile. Both of their ancestors lived during the cretaceous period and tend to get lumped together. Another analogy would be ...


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Sorry for the delay, I was low on time and didn't want to post a poor answer. Let's get into it step by step. The most important thing here is to understand that every single thing you do is a combination of many highly complicated biochemical and biophysical reactions/processes that slow down as temperature gets lower. Since any chemical reaction is a ...


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Why it can feel chilly close to trees in the evening: Water coming out of Stomata vaporises, reducing the surrounding temperature. There is normally no direct sunlight reaching the ground beneath the tree, hence the moisture content of soil is higher, giving it the "chilly feeling" If there is other vegetation (e.g. grass) growing beneath the tree,...


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The measurement of core temperature (it is the right term*) is easy using an invasive method. It is also reliable since: Core temperature is easy to measure and temperatures are relatively homogeneous throughout the trunk and head[PMCID: PMC1752199]; However, the measurement of skin temperature is highly dependent on the location of measurement and ...


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In3mo informed about oxygen content varying with temperature, and another factor is the fish metabolic rate: Standard Metabolic Rate (SMR) is the metabolic benchmark in fish. It is the metabolic rate of a resting fish at a specified temperature in the middle of its normal range. Therefore a trout's SMR15 would be the resting metabolic rate of a ...


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Here’s how it works. Every morning when the sun breaks over the horizon — no matter what time of year it is — a clock starts ticking inside the trees. After a specific number of hours, the plants’ cells start producing high levels of a molecule known as the FT protein. This protein is responsible for initiating processes that help the plant grow. But the FT ...


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Usually cell death would follow first order kinetics. $$X=X_0e^{-kt}$$ where $X$ is the number of cells at time $t$, $X_0$ is the initial number of cells and $k$ is the death rate constant. You can get the constant by solving for 90% reduction in 2 minutes. Then just substitute and get the time required for 99.99999% reduction — 10 minutes. For your ...


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The fingers and toes (for example) ARE at lower temperatures than the interior of the torso. It's why it's so easy to get frostbite on the extremities. As for temperature regulation of the testes, you have to also consider that humans evolved without clothes...i.e. The testes just "hang out" and get lots of airflow, as opposed to modern times, when they are ...


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