Organisms reproduce by two main methods. one is division, in which the animal divides and creates an exact copy of itself. what is the other main method of reproduction?
a. combination
b. division
c. fusion
d. fission

Plz genetic engineering can be applied to many fields including medicine and agriculture. which of the following is a medical application of genetic engineering? a. giving crop plants recombinant dna so that they would be resistant to herbicides. b. examining a persons pedigree to determine whether they can carry a gene for a genetic disease. c. analyzing a persons dna to see how closely they are related to another person. d. certain genes into bacteria so that they will produce a needed medicine.

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins