The gradual abundance of oxygen (by product of photosynthesis) made it possible for aerobic organisms to grow more and evolve.
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Answer:
Many parts of the cardiovascular system (including the heart) are influenced by gravity. On Earth, for example, the veins in our legs work against gravity to get blood back to the heart. Without gravity, however, the heart and blood vessels change – and the longer the flight, the more severe the changes.
Answer:
2. Alec Jeffreys
Explanation:
'DNA fingerprinting' or DNA typing (profiling) as it is now known, was first described in 1985 by an English geneticist named Alec Jeffreys. Dr. Jeffreys found that certain regions of DNA contained DNA sequences that were repeated over and over again next to each other.
A food web does not represent all the links in an actual ecosystem.
Explanation:
A food web is also called food cycle. It is understood by the natural interconnection of chain and their graphical representation. The concept is given by Charles Elton. He mentioned about the concept of food cycles in Animal Ecology but later this food cycle is replaced by food web.
Food web are limited representation of eco system. Ecologists can keep together all life forms broadly into one of the two categories which is called tropic levels. These two categories are autotrophs and heterotrophs
