Transcription (Module 7) Flashcards
Transcription is
Copying DNA’s message into RNA’s language to make a protein
What are the steps of transcription?
Identify the right part of the DNA, In INITIATION DNA opens up, in ELONGATION enzymes build the mRNA strand, and in TERMINATION the DNA molecule releases the newly synthesized mRNA
What is a phenotype?
physical characteristics of an individual
Genotype
genetic makeup of an individual, the alles possessed at a given locus
What are the three chemical components of RNA
Ribose sugar, four nucleotide basis (A,G,C,U), Phosphate
How is RNA different from DNA
RNA is unstable, decomposes rapidly, contains Uracil instead of thymine, single stranded
Why is 3’ OH tail necessary?
it is required for phosphodiester bond between nucleotides in ribose and deoxyribose
Which carbon in DNA is missing an oxygen compared to RNA?
Deoxyribose 2’oxygen, this extends the longevity of DNA because without it will be less likely to get involved in chemical reactions
What are the four types of nitrogen bases in RNA and are the purines and pyrimidines?
Purines are Adenine and Guanine and Pyrimidines are cytosine and uracil
What DNA-RNA bases are complimentary?
Purines go with Pyrimidines. therefore: G & C and A & U
What are the 3 types of RNA and there functions
mRNA actions of genes, tRNA carries amino acids during translation, rRNA puts amino acids together in chains
Only the messages of _____ are transcribed into mRNA
genes
What is the difference between purine and pyrimidine?
Purine has 2 rings, and pyrimidine has single six sided ring structure
How many genes are contained in the human genome?
22,000
How much of your DNA gets transcribed into mRNA
1%
How long is the average gene in base pairs?
3000
What are the three components of a transcription unit
gene, promoter, terminator
What is the function of the promoter
to establish where transcription starts in DNA (TATA)
Polymerase
Synthesizes polymers, there are polymerase I,II,and III.
Which polymerase is responsible for synthesizing most mRNA molecules?
Polymerase II
Interneurons
noncoding sequence, fall between the parts of the genetic code for phenotype
Exons
Coding sequence expressed nature
What happens during post transcription
5’ cap is added, longtail and adenine is added
What is alternative splicing?
the splicing of introns and exons, makes it possible for one gene to be expressed in different ways
