Answer:
Proterozoic
Explanation:
Stromatolites appear on Earth in the end of Proterozoic era because Proterozoic extended from 2500 million years to 542 million years. The stromatolites were present on earth about 542 million years ago. The stromatolites present in large number on the sea shores around the world and are considered as the Earth's first visible life form which can be seen through naked eye. These stromatolites were the first known organisms in which photosynthesis occurs and produce free oxygen..
Pues creo que comiendo? :v
Answer:
DNA ligase is an enzyme which can connect two strands of DNA together by forming a bond between the phosphate group of one strand and the deoxyribose group on another.
DNA polymerase is an enzyme that synthesizes DNA molecules from deoxyribonucleotides, which are the building blocks of DNA. The enzymes play an essential role in DNA replication, usually working in pairs to produce two matching DNA stranges from a single DNA molecule.
DNA gyrase is an essential bacterial enzyme that catalyzes the ATP-dependent negative super-coiling of double-stranded closed-circular DNA
Helicases are enzymes that bind and may even remodel nucleic acid or nucleic acid protein complexes. There are DNA and RNA helicases. DNA helicases are essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied.
Explanation:
The answer would be B. Abiotic Factors. The prefix a means not, so a biotic means not alive. Hope that helped :D