When we talk about evolution we come across the process of natural selection. Genetic variation is always required for the natural selection. A change or variation in the genes may help the individuals in a population to better adapt to the environment. Such changes may be brought by mutations or random mating in the population. Such variations help in the survival of the population by allowing them to adapt to changing environmental conditions.
Each mouse in the study has brown ears.
Problem solving I believe
The ATP molecule is a high energy molecule. When a molecule of ATP breakdown, it produces chemical as well as thermal energy. The type of energy produced is mainly depends on the application for example, if the ATP breaks down to ADP, it produces thermal energy and if couples with a cellular process it produces chemical potential.
Our body needs energy to carry out cellular functions and the energy produced in a form of ATP is taken by cells to perform functions.