THE MOLECULAR BASIS OF INHERITANCE
RECOMBINANT DNA
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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ionic bonds
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covalent bonds
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hydrogen bonds
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phosphodiester bonds
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Detailed explanation-1: -Answer and Explanation: DNA molecules with complementary sticky ends are associated by (b) hydrogen bonds. The complementary bases of the DNA bind to each other by hydrogen bonds. The A will bind to T with two hydrogen bonds and will bind to G by three hydrogen bonds.
Detailed explanation-2: -Sticky ends can hydrogen bond together, but the DNA fragments joined in this way will fall apart easily as hydrogen bonds are weak.
Detailed explanation-3: -If two DNA molecules have matching ends, they can be joined by the enzyme DNA ligase. DNA ligase seals the gap between the molecules, forming a single piece of DNA.
Detailed explanation-4: -Frequently, cohesive ends or “sticky” ends are used to describe the complementary single strands. This is so that the ends of two separate DNA molecules or the ends of one DNA molecule can “stick” together by base pairing between them.
Detailed explanation-5: -These are called sticky ends because they form hydrogen bonds with their complementary cut counterparts. This stickiness of the ends facilitates the action of the enzyme DNA ligase.