Answer:
mitochondria
Explanation:
Mitochondria is known as power house of a cell
Answer AND Explanation:
The variations that Darwin regarded as raw materials for the process of evolution have been traced to changes that occur at the gene level or the chromosome and these changes are called mutations. Organisms with beneficial mutations are able to pass them on to their offspring during reproduction. Transmission of such mutations through many generations could lead to the emergence of new species. The emergence of new species requires a long time and is also affected by the rate of mutations that a particular species undergoes. This leads to evolution.
Well considering birds follow humane rules, their selection and environment around them being thriving could effect their songs in a positive way. While a bird with a low selection of environmental stuff around them would effect their songs in a bad way giving off a more down manner.
You could make note cards on some things you need to know and put the question on one side and the answer on the other and quiz yourself. Good luck on this test though, you got this!