What did the presence of photosynthetic prokaryotes allow

a. more oxygen to enter the atmosphere
b. more water to enter the atmosphere
c. more sunlight to enter the atmosphere
d. more hydrogen to enter the atmosphere

Are salt and soap nutrients or toxins for yeast? explain.

Which statement best describes the relationship between an allele and a gene? question 1 options: an allele is a variation of a gene that can be expressed as a phenotype. an allele is the part of a gene that attaches to messenger rna molecules. an allele is a segment of a dna molecule that controls replication of a gene.

Describe how alleles and genes are related