2 - ICH - RNA

Question 1

What does RNA stand for?

Answer 1

Ribonucleic acid

Question 2

What is RNA?

Answer 2

It’s a single strand of nucleotides and does not form a helix.

Question 3

Name the 3 components of a nucleotide.

What are the differences for RNA and DNA?

Answer 3

Contains:

• Pentose sugar (deoxyribose for DNA and ribose for RNA)
• Phosphate group (from H₃PO₄)
• Nitrogenous organic base (DNA = Adenine, thymine, guanine, cytosine. RNA = Adenine, uracil, cytosine, guanine)

Question 4

Name the complementary base pairings?

Answer 4

Adenine - Uracil

Cytosine - Guanine

Question 5

What is a:

Purine

Pyrimidine

Which bases are purines and which are pyrimidines in RNA?

Answer 5

Purine = Double ringed nitrogenous bases that form a part of a nucleotide

Pyrimidine = Single ringed nitrogenous bases that form a part of a nucleotide

DNA:

• Purines = A and G*
• Pyrimidines = C and U*

Question 6

Name the type of reaction and bond formed by the joining on nucleotides.

What do you use to hydrolyse it?

Answer 6

Condentation reaction

Phosphodiester bond

Nuclease

Question 7

Name the 3 types of RNA

Answer 7

Messenger RNA (mRNA)

Transfer RNA (rRNA)

Ribosomal RNA (rRNA)

Question 8

Messenger RNA (mRNA)

Propertities, where is it found, function?

Answer 8

Messenger RNA (mRNA)

• Made in nucleus
• 3 adjacent bases called “codon”
• Carries the genetic code from the DNA in the nucleus to the cytoplasm, where it’s used in protein synthesis during translation.

Question 9

Transfer RNA (tRNA)

Propertities, where is it found, function?

Answer 9

Transfer RNA (tRNA)

• Found in cytoplasm
• CLOVER SHAPE. Has an amino acid binding site. One end has a sequence of 3 bases which are complementary to the bases in the codons. This is called “anticodon”
• Carries amino acids that are used to make proteins to the ribosomes during translation.

Question 10

Ribosomal RNA (rRNA)

Propertities, where is it found, function?

Answer 10

Ribosomal RNA (rRNA)

• Manufactured in the nucleolus.
• Helps to catalyse the formation fo peptide bonds between amino acids.
• Forms 2 subunits in a ribosome (along the proteins).

Question 11

mRNA, tRNA and rRNA summary?

Answer 11

Question 12

What is:

Transcription

Translation

Answer 12

Transcription - DNA base sequence of a gene is used to make a molecule of mRNA. (Copying)

Translation - The code on the mRNA is used to control the production of a polypeptide chain at a ribosome. (Bases → Amino acids)