In contrast to ectotherms, endotherms
a) maintain a lower metabolic rate
b) create and conserve body heat
c) need less to eat
d) are more efficient in warm enviroments

b) create and conserve body heat


Endothermy is a physiological characteristics that enables  some animals to control their body temperature unlike exothermics. This mechanism is important due to sudden change in temperature or uncontrollable conditions set by the harsh environment. 
So birds sharks salamanders and other related animals have this function.

The virus is considered to be are living item since they have hereditary material dnas or rnas. they can imitate and change. they respond to boosts, for example, radiation, chemicals, and warmth. they have antigenic properties. they are proficient to duplicate with a same hereditary constituent.