loveoforganic

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I think it boils down to metabolic activity differences. Physiological differences would be things like sweat glands though.
 

wanderer

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Cold-blooded and warm-blooded are not really the preferred terms.
The more proper terms are endotherm - an animal that generates most of its heat metabolically (birds, mammals and some other animals), and ectotherm - an animal that warms up through external sources.
You are probably familiar with how endotherms such as ourselves maintain homeostasis. Ectotherms maintain homeostasis by behavior modification (for example reptiles bask in the sun when cold, and go into shade or water to cool down.)
There's also poikilotherms (internal temperature varies) and homeotherms (internal temperature is constant)
 
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thebillsfan

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Cold-blooded and warm-blooded are not really the preferred terms.
The more proper terms are endotherm - an animal that generates most of its heat metabolically (birds, mammals and some other animals), and ectotherm - an animal that warms up through external sources.
You are probably familiar with how endotherms such as ourselves maintain homeostasis. Ectotherms maintain homeostasis by behavior modification (for example reptiles bask in the sun when cold, and go into shade or water to cool down.)
There's also poikilotherms (internal temperature varies) and homeotherms (internal temperature is constant)
cool, thanks wanderer. would endotherms and ectotherms be sub categories of homeotherms?
 

wanderer

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No. I'm not sure of the exact definitions of homeotherm and poikilotherm, which is why I didn't go any further. I know that a homeotherm has a constant body temperature, and a poikilotherm has a variable temperature, but I'm not sure where the cutoff would be.

Endotherms tend to be homeotherms, and ectotherms tend to be poikilotherms, but there are exceptions. A marine equatorial fish can be ectothermic, yet be homeothermic if the temperature of the water never changes. I'm not sure if an endotherm could ever be a poikilotherm (wiki implies that it can't), but even an endotherm's body temperature can vary when exposed to extreme temperatures, so.....

You can google these terms just to be sure or consult your gen bio text.
 

Accalia

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Man, I had a great chart on this stuff from when I took physio, but unfortunately I don't have my notes with me. Wanderer100 is right, but here are some definitions if you would like them:

Ectotherm: derives most of its heat from the environment
Poikilotherm: internal temperatures vary, often matching the ambient temperature of the immediate environment
Homeotherm: maintains body temperature over a narrow range, typically well-above ambient temperature
Endotherm: internal control of body temperature by processes that raise metabolic rate



Here are some other definitions that may be helpful, regarding how heart is gained or lost. This could be especially helpful regarding ectotherms, since there is no internal regulation of body temperature and T is essentially determined by these:
Conduction: heat loss or gain through direct contact with a substrate; the rate of heat transfer depends on Fick’s Equation KA(T2-T1)/length of heat travel, where A is equal to contact area; there is 20-30 times more conductivity to water than to air
Convection: heat gain or loss by movement of a substrate across the body
Evaporation: evaporation from body surfaces and respiratory surfaces causes heat loss because the heat of vaporization of water is 585 cal/mL; this is the only avenue for heat loss when the ambient temperature is greater than body temperature
Radiation: energy emitted in the form of waves by an atom or another particle as it goes from a higher to a lower energy state; everything radiates heat; the sun is the primary source for radiation, so when the sun is out, it causes significant heat gain, but when it is not, radiation is the most significant form of heat loss