Pair up the nucleotide bases with their complementary partners

Question 1

Pair up the nucleotide bases with their complementary partners.

Question 2

Which of the following nucleotide sequences represents the complement to the DNA strand…

Which of the following nucleotide sequences represents the complement to the DNA strand 5′-AGATCCG-3′?

a. 5′-AGATCCG-3′.

b. 3′-AGATCCG-5′.

c. 5′-CTCGAAT-3′.

d. 3′-CTCGAAT-5′.

e. 3′-TCTAGGC-5′.

Question 3

Answer to question 1

In a DNA, the nucleotide base Adenine [A] always pairs with Thymine [T]. Also Guanine[G] always pairs with Cytosine [C] 

i.e   A – T  ,    T – A ,   G – C ,    C – G.

Tis is in accordance with the Chargaff’s Rules of base Pairing. 

However, in an RNA  there is no Thymine [T] . Instead Uracil [U] is the nucleotide base.

Answer to question 2

The correct answer is (e) 3′-TCTAGGC-5′.

In DNA strands, there are four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G). Each of these nucleotides is complementary to another nucleotide and can only pair up with their respective base pair.

The following are the complementary nucleotide base pairing:

Thymine (T) pairs with adenine (A).

Adenine (A) pairs with thymine (T).

Cytosine (C) pairs with guanine (G).

Guanine (G) pairs with cytosine (C).

The complementary strand of 5′-AGATCCG-3′ will run in the 3′ to 5′ direction. This is because the DNA double-helix structure runs in an antiparallel direction. From the above guidelines, the complementary strand of the given DNA sequence can be determined. The complementary strand is 3′-TCTAGGC-5′.

Answer to question 3

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