Answer:
The oxygen revolution happened about 2.5 billion years ago. ... Then oxygen started to accumulate in the atmosphere. Oxygen is toxic to anaerobic organisms and this increase in atmospheric oxygen killed much of the life that had evolved to this point generating a huge mass extinction.
Explanation:
Answer:
D
Explanation
I have taken that quiz before
The body wall<span> of a star fish is made up of a thin cuticle, an epidermis with a single layer of cells, a thick dermis composed of connective tissue and a thin coelomic myoepithelial layer, which allows the longitudinal and circular musculature.</span>
B
Both have brown coats due to dominant B allele, genotype is different as one has recessive b allele
The answer is A. <span>Solar energy is a renewable resource because it can't be used up, but oil is a nonrenewable resource because it will eventually run out.</span>
