According to theories of how life began, how did early organic molecules begin to separate from the outside world?

the tricuspid valve is present between right atrium and right ventricle

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

answer///multiple alleles;

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.