What is true about recessive alleles? * -A randomly expressed gene
-A rare allele, only found in recessive animals
-Recessive traits only manifest when both alleles are recessive in an individual.

answer; ///(b) it is composed of four protein chains and four heme groups;

tissue

explanation:

it is actually formed by geoup of cells which is tissue

which

what is a measurement of the earth’s history divided into time periods?

> fossil record <

sedimentary rock

> geologic time scale <

radioactive elements