RNA

Question 1

rna

Answer 1

• ribosomal nucleic acid

- found as a single strand in various shapes

Question 2

difference between rna and dna

Answer 2

• rna has ribose, dna has deoxyribose
• rna has uracil not thymine
• rna is single stranded

Question 3

shapes of rna

Answer 3

• mRNA: noodle
• rRNA: balls up into glob
• tRNA: looks like letter T

Question 4

mRNA

Answer 4

• created in nucleus in process called transcription
• it is a copy of a gene that is capable of leaving the nucleus. it carries the code to the cytoplasm where it randomly bumps into a ribosome
• contains the codon

Question 5

codon

Answer 5

3 nucleotide sequence of rna

Question 6

rRNA

Answer 6

2 rRNAs join together to form 1 ribosome, the ribosome is the location of translation

Question 7

tRNA

Answer 7

will pick up specific amino acid and bring it to ribosome. tRNA contains the anti codon

Question 8

anti codon

Answer 8

3 nucleotide sequence of tRNA

Question 9

overview of flow from gene to protein in eukaryotes

Answer 9

DNA (transcription) -> mRNA (translation) -> protein

Question 10

how does transcription start

Answer 10

RNA polymerase binds to promoter region in the DNA that looks like TATA (= TATA box)

Question 11

RNA polymerase

Answer 11

• unwinds DNA and builds complementary strand

- creates mRNA, pre-mRNA or the transcript

Question 12

termination signal

Answer 12

• transcript detaches when it hits this
• AAAAAA
• this also releases mRNA

Question 13

guanosine triphosphate (GTP)

Answer 13

added to the 5’ region of mRNA before it can leave the nucleus, known as the 5’ cap

Question 14

poly A tail

Answer 14

• 150-200 A’s

- added to the 3’ end which controls the movement of mRNA through nuclear pore

Question 15

SnRNP’s (small nuclear riboproteins)

Answer 15

cut out the introns so that several genes can be transcribed at once

(1 gene can be read many different ways producing many different products depending on how the gene is spliced)

Question 16

start of translation

Answer 16

mRNA floats around cytoplasm until it hits the small subunit of a ribosome, at this point binding takes place

Question 17

what happens after mRNA attaches to ribosome (translation)

Answer 17

first tRNA arrives with amino acid methionine attaches to mRNA.
-second rRNA subunit attaches

Question 18

amino acids

Answer 18

• randomly brought to ribosome by tRNA

- put in very specific order by matching the mRNA codon to tRNA anticodon

Question 19

how many tRNAs can fit on a ribosome at once?

Answer 19

2