The classes of chordata which are warm-blooded are birds and mammals.
Explanation:
Warm-blooded animals are those which can maintain their body temperature at a constant.
These classes of chordates balance their internal body temperature with that of the outer environment. When the outer environment is cold, they increase their internal temperature by producing more heat; and when it is hot outside they reduce their internal temperature by cooling themselves.
The food consumed by a warm-blooded animal fuels to maintain a constant body temperature and hence they require more food.
Warm blooded animals cool themselves with the help of sweat glands.
The skin and other parts like fur in birds help to keep the animals warm during winter. Birds also shed their fur in hot season to keep them light. Birds migrate to warm regions during winter.
These animals have high stamina and energy to survive environmental changes. They maintain their temperature through endothermy, homeothermy or tachymetabolism.
Whale living in water is the fish which is also warm blooded because it is a mammal.
Answer:
hydrogen bond
Explanation:
by weak electrical attraction between two polar molecule hydrogen bond is developed between them
the example is water molecule in case of water two water molecules are attracted toward each other by strong hydrogen bond which is developed between highly electronegative oxygen of one water and electropositive hydrogen of another water molecule
By dying after mating in order to feed the young.
The early signs of a heart attack occur in 50% of patients that have a heart attack according to the Society of Cardiovascular Patient Care. If the early symptoms are noticed the treatment can be administered to prevent damage to the heart as the most heart damages, 85% occur in the 2 hours following the attack.