Answer:
the biggest difference is that mammals are endothermic and internally regulate their body temperature, but reptiles are ectothermic because they rely on the environment to do it for them.
Step-by-step explanation:
Ectothermic: An ectothermic animal, also commonly known as a "cold-blooded" animal, is one who cannot regulate its own body temperature, so its body temperature fluctuates according to its surroundings. The term ectotherm comes from the Greek ektos, meaning outside, and thermos, which means heat
Endothermic: An endothermic process is any process with an increase in the enthalpy H of the system. In such a process, a closed system usually absorbs thermal energy from its surroundings, which is heat transfer into the system.
Exothermic reactions transfer energy to the surroundings and the temperature of the surroundings increases. Endothermic reactions takes in energy and the temperature of the surroundings decreases.
Hope this helps
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