How do we know that some layers of the earth are solid and some liquid?

Plz ! a scientist wants to produce a cow that makes a particular human protein in it’s milk the desired protein causes blood to clot and can be used to treat hemophilia (a blood clotting disorder). which of the following would be best for the scientist to use? a. genetic crosses. b. cloning. c. selective breeding. d. genetic engineering.

Apuppy’s tendency to chew is inherited through which of the following? a. through learned behavior b. through genes c. through seasonal cycles d. through hibernation

To determine if a particular plant is homozygous or heterozygous, you would have to test cross with a