When is a recessive allele expressed in offspring? •when the offspring is heterozygous
•when the offspring has both dominant alleles
•when parents have no recessive alleles
•when two copies are present

Grape jelly so a y did you ask this question

It depends on the surface of the levels. the rougher the surface, the greater is the frictional force. for rougher surfaces, you would need to exert greater force to move the object. the concept is that, you must overcome the frictional force in order to bring the object into motion. this is the reason why we add lubricants to the joints so they could easily move. this answer was on

The first means of speeding up reactions mentioned by the speaker is raising the enzymes