The five basic needs of all animals are sunlight, water, air, food and habitat. Sunlight is the fundamental source of energy on earth. Solar energy enters the living ecosystems though the process of photosynthesis carried out by green plants and is transformed into usable chemical energy.
All animals need water to regulate various biochemical processes that go on in the body. In humans, water forms 65 percent of the body weight. Water helps to maintain the temperature of the body and also helps to remove excretory products form the body.
Animals need food to survive. The energy obtained from food is used to carry out various life sustaining processes such as respiration, digestion and excretion. Nutrition requirements take various forms. Herbivores are plant eaters, and carnivores are meat eaters.
Air provides the oxygen to sustain life. Without oxygen, respiration would not take place, making death certain.
Habitat is the natural environment in which animals live. Animals live in different habitats, and they're adapted for that particular habitat. For instance, a polar bear is adapted for living in the freezing arctic conditions, while a shark has evolved to live in an aquatic habitat. A polar bear would die in the heat if taken out of its natural habitat. A shark has gills that allow it to breath in water but would die if removed from water, its natural habitat.