Answer and Explanation:
During the whole biota history, there occurred extinctions due to different reasons.
During the Cretaceous, which took place between 145-65 million years ago, there occurred a massive extinction that eliminated most of the species on the Earth. Many of the characteristic groups of this period were affected. Dinosaurs, Plesiosaurs, Ammonites, Tricodonts, Cycas, Gynkgos, Conifers, the recent angiosperms, birds, and mammals.
The extinction was caused by the volcanic eruptions, and the unusual fall of many different asteroids, which caused important changes on the Earth´s surface. The consequent climatic change was what ended affecting all the species directly. The extinction was gradual, although it occurred in a short geological lapse of time.
Answer:
<u>A chemical bond between the phosphate group of one nucleotide and the sugar of a neighboring nucleotide holds the backbone together. Chemical bonds (hydrogen bonds) between the bases that are across from one another hold the two strands of the double helix together.</u>
Explanation:
Explanation:
Evolution is a slow natural process occurring in living organisms which explains the formation of the diversity of organisms on Earth. In simple terms, evolution explains how life survived on Earth after the origin of life but it cannot explain the origin of life. However, modern evolutionary biologists are now trying to decode the origin of life through evolutionary evidence and support that earlier form of life originated in the large oceans around 3.5 billion years ago. These organisms are simple living unicellular organisms which later evolved into the eukaryotic organisms.
Answer: rhino
Just because I said so