Hi
It is true that on the Galapagos islands Darwin observed tortoises with a dome and saddle shaped shells, you can see both in attached image.
Darwin observed that Galapagos Tortoises had the shells with different shapes depending on the Island they live, For example: The tortoises with saddle shaped shells were able to reach up to eat leaves of plants while the tortoises with dome shaped shells would not reach up and they would eat food from on ground sources. This made him think that the differences in tortoise shell is also a strong evidence that indicates that how tortoises have adapted themselves to better get their food as per the available resources and how they have evolved from same ancestral specie into two different species. This point also helped him in proposing the theory of evolution by natural selection.
Hope it helps!
Pure breeding means the same as selective breeding since you take two animals and combine their traits for certain reasons
D. Mitochondria and Chloroplast
i'm sorry if it's wrong but that should be the right answer
Ecological succession is the process of change in the species structure of an ecological community over time. The time scale can be decades, or even millions of years after a mass extinction
The answer is A.The calcium atom must bond with an atom of high electronegativity (like fluorine) because the higher electronegativity atom will bully the low electronegativity atom and take away its electrons.
These are the choices:
A. an atom with a high electronegativity, like fluorine
B. another atom with a low electronegativity, like lithium
C. another atom that would like to share electrons
D. no other atoms because it's too weak to bond with anything
