Which of the following contain organs? Choose 2 answers:
organism
cell
tissue
organ system

The spermists believed that: the male made the only hereditary contribution to the offspring the male and female traits were blended in the offspring the female made the only hereditary contribution to the offspring the male and the female made equal contributions to the next generation

Which of the following is a reason why early living organisms on earth could not have survived on the surface? 1. the lack of an ozone layer 2. the lack of oxygen in the atmosphere 3. the fact that these organisms were single-celled

What is required in the genotype of an individual to show a recessive trait? a.two recessive alleles b.at least one recessive allele c.no recessive alleles