Lecture 15

Question 1

Intron/ Exon

Answer 1

Introns are out and introvening and exons stay in and are expressed. Introns get split off and the two exons are added together.

Question 2

Spliceosome

Answer 2

A protein complex that recognizes junction between introns and exons, binds the two junctions and removes the intron as a loop

Question 3

Ribosome

Answer 3

mRNA is read by a ribsome. Where the A, P, and E sites are. makes proteins

Question 4

A Site/ P Site/ E Site

Answer 4

A site is at the 3’ end and the P site is in the middle and the E site is at the 5’ end. It makes a protein and the units shift over. A site= amino acid is added

Question 5

Small subunit/ Large Subunit

Answer 5

The small subunit binds to the large subunit.

Question 6

Codon

Answer 6

mRNA is read in groups of 3 nucleotides which is called a codon

Question 7

Reading Frame

Answer 7

it reads in groups of 3s. There are 3 different ways it can be read but one one way is right.

Question 8

Shine-Dalgarno sequence

Answer 8

It is GGAGG and it is part of the start sequence. So the promoter finds the GGAGG and then finds the next AUG and starts coding from there. Because there are less GGAGGs in the cell then AUG and AUG can be part of the coding. This is also only in Prokaryotes.

Question 9

tRNA

Answer 9

any of a class of small, cloverleaf forms of RNA that transfer unattached amino acids in the cell cytoplasm to the ribosomes for protein synthesis.

Question 10

Anticodon loop

Answer 10

A sequence of three adjacent nucleotides in transfer RNA that binds to a corresponding codon in messenger RNA and designates a specific amino acid during protein synthesis.

Question 11

Charged tRNA

Answer 11

It is carrying an amino acid

Question 12

Aminoacyl-tRNA Synthetase

Answer 12

The correct amino acid is added to tRNA by this. It is where the tRNA and the particular amino acid bind and form together.

Question 13

Initiation Complex

Answer 13

It is the E, P, A sites

Question 14

Elongation

Answer 14

Involves lots of translation factors. Uses GTP and transpeptidation and translocation

Question 15

Transpeptidation

Answer 15

Making a peptide bond

Question 16

Translocation

Answer 16

Movement of ribosme

Question 17

Stop Codon

Answer 17

There are 3 different stop codons. The coding is stopped when the promoter reaches this codon

Question 18

Release Factor

Answer 18

Protein that allows for the termination of translation. Binds to the tRNA and causes the ribosomes to fall apart. Uses the stop codon

Question 19

Readthrough

Answer 19

Sometimes a tRNA does not recognize a stop codon, but the sequence continues and it will stop at the next one. Thats how proteins evolved.

Question 20

“Coupled” Transcription and translation

Answer 20

As RNA is being made proteins are being made from RNA