Hemophilia is caused by . codominant alleles for the trait
a missing copy of one chromosome
a recessive allele on the X chromosome
an extra copy of a chromosome

There are six elements that make up most of the human body. which of the following is not one of these six elements?

In which situations is the principle of cross-cutting relationship useful in determining relative age?

Jasmine, at 33 months of age, is able to engage in some self-care behaviors but still has trouble with tasks such as putting on socks. a few months later, she accomplishes this same task relatively easily. the change in abilities is most likely due to