Four unifying principles form the foundation of modern biology<span>: cell theory, evolutionary theory, the gene theory and the </span>principle<span> of homeostasis. These </span>four principles<span> are the founding principles of each category of biology</span>
a chemical landfill is where chemical waste is stored once it has been used
if it is secure it means that the waste cannot pollute the environment through water, air etc
The horse and donkey, though closely related by sharing a common ancestor, are different species. They have different number of chromosomes hence pairing of homologous chromosomes during fusion of gametes becomes complicated. The mule will have an extra chromosome from the horse hence will have abnormalities such as sterility. A Mule is unable to reproduce due to this same phenomenon. Homologous chromosomes are not well paired for meiosis I.
