I am not sure but I am guessing carbon and nitrogen :)
The components of the urinary system are the kidneys, ureters, urinary bladder, and urethra.
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in heritable traits of a population over time. The term "natural selection" was popularised by Charles Darwin who compared it with artificial selection, now more commonly referred to as selective breeding.
<h2>When too walk your dog you are using energy from the sunlight to power this activity</h2>
Explanation:
The ultimate source of energy in the ecosystem is the sun. When we take our dog for a walk, we are utilizing energy stored in our body that we obtained food. We must have obtained that from either plants or animals. The animal in turn must have obtained its food from plant. Plants are the organisms in the food chain who can convert the energy from the sun into the chemical energy. So, we can say that when we walk our dog we use energy from the sunlight to power this activity.
