Cretaceous extinction also known as Paleogene extinction was a period of time when suddenly around three quarter of the animal and plant species began to get extinct from the land. The event happened around 66 million years ago and is considered as the end of cretaceous era that lead to the beginning of Mesozoic era.
Reasons for the mass extinction:
- Scientists think that a major asteroid or comet hit the surface of earth which deteriorated the earth’s environment, especially by making it difficult for plants to perform the process of photosysnthesis. This is called as Impact hypothesis and scientists think that it was the reason of extinction of so many species because they found debris of asteroid in the land.
- There could also be some other reasons like climate changes,volcanic eruptions and changes in the sea level which made the environment unfavorable for the survival of living organisms.
- One of the best known organism that is thought to extinct in cretaceous period was dinosaur.
Extinction of Dinosaurs:
As stated above the exact cause of dinosaur extinction can not be stated with confidence. This is because cretaceous period was the time when so many unfavorable circumstances took place like diseases, geologic events ,climate change etc.
However, the most believed theory is that some Asteroid hit the surface of earth and turned the climate very very old. Therefore, those amazing creatures were not able to survive that climate.
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If the water is salty like in the oceans, as the water freezes the salt is pushed out making the water denser making it sink to the bottom in a current to keep climate cool and the surface currents warm the artic. The way it effects life is, it makes a passageway over the freezing water across so that you won't freeze to death swimming. And it helps migration too. The Sub-zero waters keep algae from growing, which is good because most are hibernation.
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Answer:
Through the photolysis of water molecules
Explanation:
<em>When the electrons in photosystem II gets excited, released and travel down to the electron transport chain, the electrons are replaced by the electron released by the cleavage/photolysis of water.</em>
<em>Water molecule is cleaved resulting in the formation of hydrogen ion, oxygen gas and electrons. The electrons then replace those lost by photosystem II.</em>
Answer:
The breathing rate increases.