Answer: The DNA double helix is held together by two types of bonds,
covalent and hydrogen.
Explanation: Covalent bonds occur within each linear strand and strongly
bonds the bases, sugar and phosphate groups.
Answer:
Lack of food sources, the lack of habitat, competition and evolving ways to compete.
Explanation:
Lack of food sources, the lack of habitat, competition and evolving ways to compete are the ecological conditions that is responsible for the rapid diversity of some lineages. With the passage of time, changes occurs in the lineages due to climate change which causes some species to extinct and some to evolve which attains adaptability to the environment. Due to climate change food is unavailable to the organisms which is the main cause of its extinction.
