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Flashcards in e x a m III Deck (52):
1

which RNAs are functional?

tRNA & rRNA

2

how many amino acids make up a codon?

three

3

what is the sequence of the start codon?

AUG

4

what are the three stop codons?

UGA UAG UAA

5

what does is mean that the genetic code is degenerate?

some amino acids are encoded by more than one codon

6

how many combinations are there of amino acids?

64

7

what is the function of tRNAs

translate the genetic code into amino acid sequence

8

which RNAs make up the majority of RNAs?

functional RNAs

9

what is the function of tRNA

serves as the adapter to amino acids
carries amino acids to the proper codon

10

tRNA synthetases

add charge to amino acid

11

IF3

binds the large ribosomal subunit to the smaller one
allows mRNA to bind to smaller subunit

12

shine-delgarno

for correct positioning for initiation

13

IF2

binds GTP & Met-tRNA
brings them to the P site

14

what happens when the large ribosomal subunit & small ribosomal subunit are bound?

IF2 & IF3 are released

15

elongation factor EF-Tu

escorts tRNA into the A site

16

EF-Ts

catalyzes release of EF-Tu and GDP from ribosome

17

peptidyl transferase

catalyzes the formation of a peptide zone between amino acids at the A & P sites

18

EF-G

catalyzes the release of uncharged tRNA
moves the amino acid sequence over in the mRNA

19

termination

polypeptide is discharged
ribosome is dissociated

20

how many amino acids are there?

20

21

primary structure of amino acids

specific amino acid sequence

22

secondary structure of amino acids

alpha helicies
beta sheets

23

tertiary structure of an amino acid

spatial arrangement of amino acids
from alpha helix & beta sheets

24

quaternary structure of an amino acid

spatial relationship of a polypeptide
how they associate into a multi-subunit molecule

25

one gene codes for...

one protein

26

anti-codon

complimentary tRNA to strand of mRNA

27

the genetic code is...

evolutionary conserved

28

zinc finger motifs

changes the three amino acids in a hormone receptor

i.e. - glucocorticoid --> estrogen receptor

29

how does a Zn-motif protein work?

amino acid sequence is held together by zinc atom

alters interaction of dna

30

gene mutations alter protein function how?

the Zn finger domain would not exist
it would unravel and not bind to DNA

31

what is the consequence of protein mutations

reduced protein function
cystic fibrosis

32

x-ray crystallography

protein fragments are crystallized
x-rays are scattered through the crystal
atoms diffract the crystal
mathematical analysis determines the structure of the protein

33

recombinant DNA

engineered DNA from different sources

34

making recombinant DNA

isolate target DNA
cut DNA
insert name vectors

35

clone

identical copy of dna

36

vector

carrier molecule of gene of interest

37

insert

DNA molecule of interest

38

restriction endonucleases

enzymes that cut DNA
produce sticky or blunt ends

39

sticky ends of the same size are...

complimentary

40

dna library construction

recombinant dna is cut (enzymes or mechanically)

introduced into bacteria

bacterial colonies are grown to amplify dna

41

what does an antibiotic do in the case of recombinant dna?

the antibiotic will kill bacteria WITHOUT the plasmid

42

cDNA libraries are used for...

the ENTIRE genome

43

how to make cDNA library

1. isolate RNA
2. obtain cDNA from RNA through reverse transcriptase
3. transform DNA into vector

44

difference between cDNA library and PCR

cDNA = entire genome
PCR = specific gene

45

PCR steps:

1. heat DNA to separate strands
2. lower temp for hybridization of primers
3. primers synthesize complimentary DNA
4. repeat until there are TONS of copies of the same gene

46

sanger DNA sequencing

dna sequencing through dedioxynucleotides and RNA polymerase

47

reverse genetics

START with gene of interest
use recombinant DNA to mutate gene
examine effects of mutated gene on protein

48

forward genetics

select phenotype of interest
randomly introduce mutations
identify the gene responsible for the mutation

49

site-directed mutagenesis

methylated dna is digested by enzymes
only newly created dna is left

50

deletion mutagenesis

necessary domain is deleted
gene is non functional
if successful, florescence isn't produced

51

gene knockouts

substitute a non functional allele for a normal allele

52

structural genomics

molecular organization of genome