Answer:
Many scientists were skeptical of the endosymbiotic hypothesis because it didn't seem to fit into the theory of evolution as it was understood then. Between 1900 and 1950, biologists made many key discoveries in the field of genetics by focusing on small, random changes in DNA — mutations — that occur when a cell reproduces.
Explanation:
Six thousand reindeer once lived on a remote island in the Bering Sea
that was briefly their paradise. In what has become a classic story of
wildlife boom and bust, no reindeer live on St. Matthew Island now.
Three scientists just looked back at the St. Matthew's reindeer herd and
found that an extreme winter probably pushed the stressed animals to
their deaths.
Answer:
The androecium is the sum of all the male reproductive organs, while the gynoecium is the sum of the female reproductive organs.
and If all four whorls are present, the flower is described as complete. If any of the four parts is missing, the flower is known as incomplete.