DNA, RNA and Protein Synthesis

HideShow resource information
  • Created by: becky
  • Created on: 09-03-16 21:41
How is DNA stored in eukaryotes?
Contain linear DNA in the form of chromosomes in the nucleus, DNA double helix wound around proteins to form histones and coiled further into a chromosome
1 of 21
How is DNA stored in prokaryotes?
Short and circular DNA, no histones, condenses by supercoiling
2 of 21
What is a gene?
Sequence of DNA bases that code for a polypeptide or functional RNA
3 of 21
What do the triplet codons code for?
Amino acids
4 of 21
What is functional RNA?
Any RNA molecule other than mRNA
5 of 21
What are introns?
A section of a gene that doesn't code for an amino acid
6 of 21
When and how do eukaryotes remove their introns?
During protein synthesis by a process called splicing pre-mRNA
7 of 21
What are exons?
Genes that do code for amino acids
8 of 21
What is an allele?
A different version of a gene, e.g. for eye colour, blue and brown would be different alleles of the same gene
9 of 21
What are homologous chromosomes?
Matching pairs of chromosomes, same size and contain the same genes, however they could have different alleles
10 of 21
What are the two main stages of protein synthesis?
Transcription and translation
11 of 21
What is transcription?
Where DNA is copied into mRNA
12 of 21
What is translation?
Where mRNA joins a ribosome to synthesise the protein
13 of 21
What is mRNA?
Made during transcription, carries genetic code from DNA to ribosomes, single stranded molecule
14 of 21
What is tRNA?
Involved in translation, carries amino acids that are used to make proteins to the ribosomes, single strand that is folded into a clover shape held by hydrogen bonds
15 of 21
What happens during the first step of transcription?
RNA polymerase attaches to the DNA, hydrogen bonds holding the double helix break and the strands separate, one acts as a template
16 of 21
What happens during the second step of transcription?
Complementary RNA is formed when free bases are attracted to the template strand
17 of 21
What happens during the third step of transcription?
RNA polymerase moves along the DNA, separating the strand but assembling the mRNA strand, hydrogen bonds reform in the DNA to put the double helix back together
18 of 21
What happens during the fourth step of transcription?
RNA polymerase reaches the stop codon and stops making the mRNA, also detaches itself from the DNA, mRNA moves out of the nucleus through a nuclear pore and to a ribosome
19 of 21
What happens during translation?
mRNA attaches to ribosome, tRNA carries amino acid to it, requires energy for the bonds to form, tRNA finds start codon and produces the amino acid then moves off, second tRNA attaches to next codon making this amino acid, amino acids form chain
20 of 21
When does translation stop?
When the tRNA reaches a stop codon
21 of 21

Other cards in this set

Card 2

Front

How is DNA stored in prokaryotes?

Back

Short and circular DNA, no histones, condenses by supercoiling

Card 3

Front

What is a gene?

Back

Preview of the front of card 3

Card 4

Front

What do the triplet codons code for?

Back

Preview of the front of card 4

Card 5

Front

What is functional RNA?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all DNA, genetics and evolution resources »