2.2 Protein Synthesis

Question 1

What are proteins made up of?

Answer 1

Proteins are made up of molecules called amino acids. There are 20 different kinds of amino acids in our body.

Question 2

Genes

Answer 2

Genes are sections of DNA that contain instructions for the number and order of amino acids to create a functioning protein.

Question 3

Two Stages of Protein synthesis

Answer 3

1. Transcription
2. Translation

Question 4

Transcription

Answer 4

Occurs in the nucleus. DNA is transcribed to mRNA.

Question 5

mRNA

Answer 5

A single-stranded molecule that can travel out of the nucleus into the cytoplasm, it carries the genetic code for a gene (messenger).

Question 6

Translation

Answer 6

Occurs in protein-making ‘factories’ called ribosomes that are found in the cytoplasm. mRNA is translated into a protein chain.

Question 7

What are the 4 bases of mRNA and how do they pair?

Answer 7

Adenine, Uracil, Guanine and cytosine. A pairs with U and G pairs with C.

Question 8

tRNA

Answer 8

tRNA are molecules that carry amino acids.

Question 9

How many bases are read to make an amino acid?

Answer 9

The base on mRNA are read in groups of three, eg ‘AUG’. Each triplet codes for an amino acid eg AUG = Methionine.

Question 10

Codon

Answer 10

A group of three bases is called a codon which codes for a specific amino acid.

Question 11

Anticodon

Answer 11

An anticodon is in the tRNA and they are complementary to the codons on mRNA. This ensures they can deposit amino acids in the right order.

Question 12

Polypeptide/peptide chain

Answer 12

A single linear chain of many amino acids, held together by peptide bonds