Structures of Ribonucelic Acid

Question 1

How is the coded information on the dna in the nucleus transferred into proteins ?

Answer 1

Sections of dna code are transcribed onto a single stranded molecule called ribonucleic acid

Question 2

What is messenger rna

Answer 2

It transfers dna code from the nucleus to the cytoplasm

Question 3

How does mRNA leave the nucleus

Answer 3

Through the nuclear pores to enter the cytoplasm

Where the coded information that it contains is used to determine the sequence of amino acids in the proteins

Question 4

What is a codon

Answer 4

The sequence of three bases on mRNA that codes for a single amino acid

Question 5

What is the genome

Answer 5

The complete set of genes in a cell, including those in the mitochondria and/or chloroplasts

Question 6

What is the complete proteome

Answer 6

The full range of proteins produced by the genome

Question 7

What is the proteome

Answer 7

The proteins produced by a given type of cell under a certain set of conditions

Question 8

What’s the structure of RNA

Answer 8

It is a polymer made up of repeating mononucleotide sub-units. It forms a single strand in which each nucleotide is made up of :

The pentode sugar ribose

One of the organic bases (adenine, guanine, cytosine, uracil )

A phosphate group

Question 9

What are the 2 types of rna that are important in protein synthesis

Answer 9

Messenger rna - mRNA

Transfer rna -tRNA

Question 10

What’s the structure of mRNA

Answer 10

• long strand arranged in a single helix

- the base sequence of dna is determined by the sequence of bases on a length of dna in a process called transcription

Question 11

What does mRNA do when it leaves the nucleus

Answer 11

It associates with the ribosomes and acts as a template for protein synthesis

Question 12

How mRNA structure suited to its function

Answer 12

As if posses information in the form of codons ( 3 bases that are complementary to a triplet in dna). The sequence of codons determines the amino acid sequence of a specific polypeptide that will be made.

Question 13

What is tRNA

Answer 13

A relatively small molecule that is made up of around 80 nucleotides.

Question 14

What’s the structure of tRNA

Answer 14

Single stranded chain folded into a clover leaf shape

With one end of the chain extending beyond the other

Question 15

Why is one end of the chain extending beyond the other

Answer 15

This is the part of the tRNA molecule to which an amino acid can easily attach

Question 16

What’s at the opposite end of the tRNA molecule

Answer 16

A sequence of 3 other organic bases, known as anticodon

Question 17

Why does there need to be as many tRNA molecules as there are coding triplets

Answer 17

As genetic code is degenerate

Question 18

Each tRNA is specific to one amino acid. What does this m an

Answer 18

It has an anticodon that is specific to that amino acid

Question 19

Distinguish between the structure of mRNA and the structure of tRNA

Answer 19

mRNA is larger, has a greater variety of types and is shaped as a long single helix

tRNA is smaller, has fewer types and is clover leafed shape

Question 20

State ways in which the molecular structure of rna differs from dna

Answer 20

Rna is smaller then dna

Rna is usually a single strand and dna a double helix

Sugar in rna is ribose, sugar in dna is deoxyribose

In rna the base uracil replaces thymine

Question 21

Distinguish between a codon and an anticodon

Answer 21

A codon is the triplet of bases on messenger RNA that codes for an amino acid. An anticodon is the triplet of bases on a transfer RNA molecule that is complementary to a codon

Question 22

What pairs with the 3 complementary organic bases that make up a codon on mRNA in protein synthesis

Answer 22

An anticodon