True or False: Purine is connected to pyrimidine using oxygen bonds.​

False

Explanation:

In DNA double helix molecule, there are four types of nitrogenous bases: adenine, guanine, cytosine and thymine. Purines (i.e., adenine, guanine) and pyrimidines (i.e., cytosine and thymine) hold DNA strands together via hydrogen bonds. In base pairing, guanine always pairs with cytosine through 3 hydrogen bonds, while adenine always pairs with thymine by 2 hydrogen bonds. Hydrogen bonds are a type of dipole–dipole interaction where a hydrogen atom is covalently bonded to a very electronegative atom (e.g., Nitrogen or Oxygen).

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."

answer; i believe that the correct answer is (lung);