Answer:
D. geographic isolation.
Explanation:
As the Grand Canyon formed, it became a physical barrier to the mixing of squirrels from its northern and southern sides. Each squirrel population was confined to a single side. This type of separation is referred to as geographic isolation.
Origin of species by means of natural selection
Answer:
Disease
Explanation:
More people that catch the disease, the more people get it because there is more to spread toword
Answer:
3. An Apple Turning Brown
Explanation:
When an apple is cut (or bruised), oxygen is introduced into the injured plant tissue. When oxygen is present in cells, polyphenol oxidase (PPO) enzymes in the chloroplasts rapidly oxidize phenolic compounds naturally present in the apple tissues to o-quinones, colorless precursors to brown-colored secondary products.
Answer:
The correct answer is - a positive feedback loop
Explanation:
Oxytocin is a peptide hormone that is released during labor in women which contracts the uterus and n increase of the oxytocin causes more release of oxytocin hormone to increase the contraction more strongly.
Oxytocin shows a positive feedback loop as its release leads to more of the oxytocin release by stimulates its more release. Most of the hormones show negative feedback release.