The Structure of mRNA and tRNA

Question 1

Like DNA, the nucleic acid RNA (ribonucleic acid) is a

Answer 1

polynucleotide – it is made up of many nucleotides linked together in a long chain

Question 2

Like DNA, RNA nucleotides contain the nitrogenous bases

Answer 2

adenine (A), guanine (G) and cytosine (C)

Question 3

Unlike DNA, RNA nucleotides never contain the nitrogenous base

Answer 3

thymine (T) – in place of this they contain the nitrogenous base uracil (U)

Question 4

Unlike DNA, RNA nucleotides contain the pentose sugar

Answer 4

ribose (instead of deoxyribose)

Question 5

Unlike DNA, RNA molecules are only made up of one polynucleotide….

Answer 5

strand

Question 6

Each RNA polynucleotide strand is made up of

Answer 6

alternating ribose sugars and phosphate groups linked together, with the nitrogenous bases of each nucleotide projecting out sideways from the single-stranded RNA molecule

Question 7

The sugar-phosphate bonds (between different nucleotides in the same strand) are

Answer 7

covalent bonds known as phosphodiester bonds
These bonds form what is known as the sugar-phosphate backbone of the RNA polynucleotide strand

Question 8

The phosphodiester bonds link the

Answer 8

5-carbon of one ribose sugar molecule to the phosphate group from the same nucleotide, which is itself linked by another phosphodiester bond to the 3-carbon of the ribose sugar molecule of the next nucleotide in the strand

Question 9

n example of an RNA molecule is messenger RNA (mRNA), which is the

Answer 9

copy of a gene that encodes a specific polypeptide

Question 10

what are the types of rna

Answer 10

messenger RNA (mRNA), Two other examples are transfer RNA (tRNA) and ribosomal RNA (rRNA)