Protein Synthesis

Question 1

What does DNA store a genetic code for?

Answer 1

Building proteins

Question 2

How does DNA store a genetic code for building proteins?

Answer 2

Each group of 3 bases (eg. ACT, AGG, GAC) codes for an amino acid. The order of these bases causes amino acids to be joined in a certain order in a protein determining what type of protein it is.

Question 3

What are the 2 processes of protein synthesis?

Answer 3

1. Transcription
2. Translation

Question 4

What is protein synthesis?

Answer 4

The process of producing a protein from DNA

Question 5

Where does transcription occur?

Answer 5

In the nucleus

Question 6

Describe the process of transcription:

Answer 6

DNA contains the genetic code for making a protein, but it cannot move out of the nucleus as its too big
- The mRNA nucleotides themselves are then joined together, creating a new strand called the mRNA strand. This is a template of the original ONA.
- An enzyme called RNA polymerase binds to non-coding DNA located in front of a gene and the DNA strand
- The 2 strands of DNA pull apart from each other, and RNA polymerase allows mRNA nucleotides (messenger RNA) to match to their complementary base strand.

Question 7

In protein synthesis what are DNA bases used for?

Answer 7

To make a strand of RNA

Question 8

Describe the process of Translation:

Answer 8

• The mRNA then moves out of the nucleus to the cytoplasm and onto structures called ribosomes. At the ribosomes, the bases on the MRNA are read in 3s (triplets) to code for an amino acid
• The corresponding amino acids are brought to the ribosomes by carrier molecules called tRNAs (transport RNAs)
• These amino acids connect to form a polypeptide (amino acids linked by peptide bonds)
• when the chain is complete the protein folds to form a unique 3D structure, which is the final protein.