What is transcription biology GCSE?
Transcription. When a gene is to be expressed, the base sequence of DNA is copied or transcribed into mRNA (messenger RNA). This process takes place in the nucleus and occurs in a series of stages. The two strands of the DNA helix are unzipped by breaking of the weak Hydrogen bonds between base pairs.
What is transcription in genetics?
Transcription is the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA). The newly formed mRNA copies of the gene then serve as blueprints for protein synthesis during the process of translation.
What happens during transcription BBC Bitesize?
Transcription. The DNA code for a protein remains in the nucleus , during transcription but a copy, called mRNA, moves from the nucleus to the ribosomes where proteins are synthesized during translation in the cytoplasm .
How does a gene code for a protein GCSE?
Each gene leads to a set of instructions to create a specific protein. These proteins are vital as it controls many aspects of the cell. The bases must group together in triplets in order for genes to code for proteins. Each of these triplets of bases codes for a specific type of amino acid.
Where are amino acids joined together?
peptide bonds
Within a protein, multiple amino acids are linked together by peptide bonds, thereby forming a long chain. Peptide bonds are formed by a biochemical reaction that extracts a water molecule as it joins the amino group of one amino acid to the carboxyl group of a neighboring amino acid.
How is Blue Eye Colour Synthesised?
There are pairs of chromosomes in the nucleus of a body cell. The chromosomes in a pair carry the same genes in the same places. Different versions of the same gene are called alleles. For example, the gene for eye colour has an allele for blue eye colour and an allele for brown eye colour.
What types of bonds are created during the process of transcription?
During transcription, a ribonucleotide complementary to the DNA template strand is added to the growing RNA strand and a covalent phosphodiester bond is formed by dehydration synthesis between the new nucleotide and the last one added.
What is the difference between mitosis and meiosis GCSE?
Mitosis produces identical diploid body cells for growth and repair. Meiosis produces haploid non-identical sex cells, or gametes . These fuse to form a diploid fertilised egg cell during fertilisation.
What is noncoding DNA GCSE biology?
The genome within eukaryotic cells contains many non-coding sections of DNA. Non-coding DNA does not code for any amino acids.
What does transcription and translation mean in GCSE Biology?
First, you will be asked to transcribe it – this means you are copying it from one place to another (eg from a textbook to your notebook) (TRANSCRIPTION). You would then translate the word into English, using a dictionary (TRANSLATION).
What happens in the transcription stage of protein synthesis?
In the transcription stage of protein synthesis, the section of the DNA molecule where the gene is located (the gene coding for a particular polypeptide) unwinds – the hydrogen bonds between the complementary base pairs break, causing the two DNA strands to ‘unzip’
Where does the template molecule in transcription go?
The template molecule is called Messenger RNA or mRNA. The mRNA moves out of the nucleus and into the cytoplasm. The mRNA molecule attaches to a ribosome in the cytoplasm. Carrier molecules, called Transfer RNA or tRNA, bring amino acids to the ribosome. Each of these amino acids is called a triplet.
How are double stranded DNA molecules used in transcription?
So in transcription, there is a double stranded DNA molecule. The molecule unravels so the strands are separate. One of the strands is going to be copied. An mRNA molecule forms that is complementary to one of the strands. This will then act as a template strand, where it will undergo translation at the ribosome.