The Precambrian era envelopes the major bulk of the history of the Earth, beginning from the creation of the planet approx 4.5 billion years ago and terminating with the origination of composite, multicelled forms of life approximately 4 billion years after.
The Precambrian refers to the earliest of the geologic ages that are signified by the distinct layers of sedimentary rock. The Earth was about more than six hundred million years old when life started. The planet had cooled down from its native molten state, creating a solid crust and oceans formed by water vapor in the atmosphere.
At about three billion years ago, the atmosphere of the Earth was virtually devoid of oxygen. At approximately 2.4 billion years ago, oxygen was discharged from the seas as a waste product of photosynthesis by cyanobacteria. The levels of the gas slowly raised, attaining about 1 percent around two billion years ago.
Approximately 800 million years ago, the levels of oxygen attained about 21 percent and started to breathe life into more composite species. The oxygen-rich ozone layer was also created, protecting the surface of the Earth from the harmful solar radiation.
<span>This form of providing energy for the storage and transport within the cell is called as Mitochondria. The energy production is done threw respiration and help regulate the cellular metabolism. Mitochondria are organelle that is present in the cytoplasm, not nucleus. Exercising your body can boost the density of mitochondria.</span>
Answer:
Bacteria that are non-controlled or destroyed by antibiotics are antibiotic-resistant bacteria. In the presence of an antibiotic, they will live and even develop. At least certain antibiotics can become immune to most infection-causing bacteria.
Explanation:
Some bacteria are immune to such antibiotics naturally. In most species found within the human digestive system, for example, benzylpenicillin has very little impact.
Answer:
Option 2.
Explanation:
The fossil proof for the human-chimpanzee last common ancestor (LCA) is rare and scarce due to: These apes lived in an environment of tight or narrow range that was not preserved well in the fossil record.
Fossil monkeys and prosimians were rare in the Miocene, however, apps were normal and dominant. Option 1 is inaccurate.
The majority of the apps known from the mid-Miocene are Old World monkeys, who are from an unexpected Linnaean family in comparison to we are is an incorrect statement so it is inaccurate.
The LCA lived in the Paleocene, a time from which we have got a number of the fossil record. so Option 3 is incorrect
Thus, the correct answer is - These apes lived in an environment of tight or narrow range that was not preserved well in the fossil record.