B1.2.2 - Transcription and Translation

Question 1

Why is a copy of DNA made?

Answer 1

DNA cannot leave the nucleus as it is too large, so a copy of the DNA is made called mRNA (messenger RNA). This is like a single strand of DNA.

Question 2

What is transcription?

Answer 2

Transcription is the process of mRNA being created. The DNA around a gene unwinds so both strands are separated. One strand is used as a template. Complementary bases attach to the strand being copied. However, there is no Thymine in RNA, so Uracil attaches to Adenine instead. Now, mRNA is formed

Question 3

What does the mRNA do from that point?

Answer 3

It travels to the ribosomes which are in the cytoplasm. This is where the proteins will be made

Question 4

How are proteins determined?

Answer 4

Proteins are made from Amino Acids. Different amino acids join together to form different proteins. The nucleotides determine which amino acids are made, which determine which proteins are made.

Question 5

How are proteins made?

Answer 5

Proteins are made by a process called Translation. This works by the mRNA attaches to a ribosome. Here, the nucleotide sequence is interpreted and the new protein is made.

Question 6

Describe the process of translation

Answer 6

The ribosome reads the nucleotides on the mRNA in groups of three. These groups are called base triplets (or codons). Each triplet codes for a specific amino acid. The ribosome continues to read the triplet code, adding more and more amino acids. The amino acids join together in a chain. This is a protein

Question 7

What does the sequence of amino acids also determine?

Answer 7

How the protein folds