The answer is: The sun is called the ultimate source of energy because it is the source of almost all energies of the earth. Plants convert light energy from the sun into chemical energy (food) by the process of photosynthesis. Animals eat plants and use that same chemical energy for all their activities.
Low pressure systems lead to rain
Red blood cell, heart tissue, circulatory system
<span>Malpighian</span>
These excretory organs are vital parts and accessories for the organism to survive and maintain homeostasis. Homeostasis is the process by which an organism maintains the internal environment of itself by obtaining nutrient, converting it into energy and excreting wastes.