What are the answer choices?
Answer:
This can be caused by mating differences, sterility or environmental barriers that eventually lead to the adaptive splitting into two species. ... However, reproductive isolation is not sufficient but internal barriers to gene flow are required for speciation to evolve.
Explanation:
I hope this helps I'm not so good at explaining.
Answer:
for example down syndrome or trisomy 21 is a common genetic disorder that occurs when a person has 3 copies of chromosome 21 there are many other promotional abnormality is including tunnel syndrome klinefelter syndrome
Explanation:
I hope what I have drawn on the picture will help you understand:)
