Answer:
The polio strains cannot reproduce because they are weakened.
A genotype is the genetic coding of a trait, so it's a paired combination of genes. A genotype has two alleles, which can be dominate or recessive, but overall the answer should be <span>a paired combination of genes</span>
Answer:
Photosynthesis
Explanation:
Photosynthesis is the process by which green plants use sunlight to produce their food
The period during which the presence of stromatolites decline is the Proterzoic period. Stromatolites are widely distributed sedimentary structures consisting of laminated carbonate or silicate rocks, produced over geologic time by the trapping, binding, or the precipitating of sediment by groups of microorganisms, primarily cyanobacteria.