Transcription & Translation

Question 1

Beadle and Tatum

Answer 1

One gene, one protein theory

Question 2

Nirenberg

Answer 2

amino acids are coded by all 64 codons

Question 3

Degenerate code

Answer 3

Some amino acids have multiple codons

Question 4

Wobble pairing

Answer 4

Third letter in codon is variable

Question 5

Transcription

Answer 5

DNA -> RNA

Question 6

Template strand versus coding strand

Answer 6

Template strand is read to synthesize DNA
Coding strand contains exact sequence for mRNA except with uracil

Question 7

RNA Polymerase 

Answer 7

Enzyme synthesizes primary RNA transcript from template DNA strand

Question 8

Transcription initiation

Answer 8

RNA identifies specific starting DNA codon

Question 9

Transcription Elongation

Answer 9

Ribonucleotide added to 3’ end

Question 10

Transcription termination

Answer 10

RNA polymerase stops when it encounters terminating stop codon

Question 11

mRNA

Answer 11

Messenger RNA
Carries DNA code for protein

Question 12

rRNA

Answer 12

Ribosomal RNA
Composes ribosome 

Question 13

tRNA

Answer 13

Transfer RNA
Carries amino acids to ribosome for translation 

Question 14

Signal recognition particle

Answer 14

Composed of RNA and protein
Guides mRNA to rough ER

Question 15

Holenzyme

Answer 15

Core polymerase plus sigma for elongation

Question 16

Transcriptional unit

Answer 16

Extends from promoter to terminator

Question 17

Transcription bubble

Answer 17

RNA polymerase
DNA template strand
Growing RNA
Moves at 50 nucleotides per second

Question 18

Methylation

Answer 18

Tightly packs nucleosomes
Nucleosome is DNA wrapped around histone
No genes expressed

Question 19

Histone acetylation

Answer 19

Add acetyl group
Nucleosomes loosely packed
Allows genes to be expressed

Question 20

Enhancer

Answer 20

DNA sequence promotes transcription
Composed of distal control elements

Question 21

Two genes can share a promoter, but must have different what?

Answer 21

Distal control elements

Question 22

Lac Operon

Answer 22

Expressed in lactose is present and glucose is absent

Question 23

DNA binding motifs

Answer 23

Regions of regulatory proteins that bind to DNA

Question 24

RNA polymerase I

Answer 24

rRNA

Question 25

RNA polymerase II

Answer 25

mRNA mRNA initiation requires transcription factors which bind RNA polymerase to a promoter

Question 26

RNA polymerase III

Answer 26

tRNA

Question 27

Pre mRNA splicing

Answer 27

Modify initial RNA 1) add caps to 5’ and 3’ ends 2) remove non doing sequences via splicing

Question 28

Introns

Answer 28

Non coding sequences

Question 29

Exons

Answer 29

Coding sequences

Question 30

snRNA

Answer 30

Small nuclear RNA Removes introns and splice exons to produce final mRNA

Question 31

Spliceosome

Answer 31

Final mRNA + Proteins

Question 32

Translation

Answer 32

RNA -> amino acids -> protein

Question 33

Aminoacyl tRNA synthase

Answer 33

Adds amino acid to the accepter arm of tRNA

Question 34

Anticodon loop

Answer 34

Loop on tRNA Contains complementary nucleotides sequences for mRNA codons

Question 35

A site

Answer 35

tRNA binds to growing polypeptide

Question 36

P site

Answer 36

Binds tRNA that carried last amino acid in chain

Question 37

E site

Answer 37

Temporary binds empty tRNA Till it goes to pick up another amino acid

Question 38

Ribosomes

Answer 38

Decode mRNA and use amino acids to build proteins

Question 39

Peptidyl transferase

Answer 39

Enzyme forms peptide bond between amino acids

Question 40

Prokaryote initiation

Answer 40

Initiation complex 1) initiator tRNA charged with N-formylmethinine 2) Ribosomal subunit 3 mRNA strand

Question 41

Ribosomal binding sequence

Answer 41

mRNA complementary to rRNA

Question 42

Prokaryote elongation

Answer 42

Add amino acid If A site anticodon is complementary to A codon, the tRNA binds Ribosome travels 5’ -> 3’

Question 43

Where does transcription occur in eukaryotes?

Answer 43

Cytoplasm Rough endoplasmic reticulum

Question 44

Signal sequences

Answer 44

Beginning of polypeptide sequence Binds to signal recognition particle

Question 45

What allows ribosome to bind to rough ER?

Answer 45

rough ER protein recognizes signal sequence and signal recognition particle

Question 46

Protein degradation

Answer 46

regeneration cycle Proteins constantly produced and degraded Lysosomes have proteases to break down proteins

Question 47

Altered jeans

Answer 47

Mutation

Question 48

Point mutation

Answer 48

Alter single base

Question 49

Base substitution

Answer 49

Sub one base for another

Question 50

Nonsense mutation

Answer 50

Create unwanted stop codon

Question 51

Frameshift mutation

Answer 51

Caused by inserting or deleting single base Throws off codon triplets 

Question 52

Triplet repeat expansion mutation

Answer 52

Same codon repeats Associated with some human genetic diseases Normal= no repetition Abnormal= repetitions

Question 53

Chromosomal mutations

Answer 53

Change chromosome structure

Question 54

Deletion chromosome mutation

Answer 54

Part of chromosome is lost

Question 55

Duplication chromosomal mutation

Answer 55

Part of chromosome is copied

Question 56

Inversion chromosomal mutation

Answer 56

Part of chromosome is in reverse order

Question 57

Translocation chromosomal mutation

Answer 57

Part of chromosome is moved to a different location

Question 58

Why is it a little genetic change good?

Answer 58

Small amounts of mutation is necessary for evolution of a species