Amino acid and protein synthesis test 3

Question 1

AA biosynthesis from alpha ketogluterate

Answer 1

glutamate
glutamine
proline
arginine

Question 2

AA biosynthesis from 3-phosphoglycerate?

Answer 2

serine
glycine
cysteine

Question 3

AA biosynthesis from oxaloacetate

Answer 3

aspartate
asparagine
methionine
threonine
lysine

Question 4

AA biosynthesis from pyruvate

Answer 4

alanine
valine
leucine
isoluecine

Question 5

AA biosynthesis from phosphenolpyruvate and erythrose 4-phosphate

Answer 5

tryptophan
phenylalanine
tyrosine

Question 6

AA biosynthesis from ribose-5-phosphate

Answer 6

histidine

Question 7

T/F DNA is primarily in the nucleosome form?

Answer 7

true

Question 8

what is an intron and exon?

Answer 8

introns are non-coding

exons are coding for AAs

Question 9

All the DNA in mammals codes for proteins T/F?

Answer 9

false only 1.5% codes for proteins

25,000 human genes

Question 10

what is the regulatory/silencer region of DNA?

Answer 10

binding of proteins that promote or inhibit transcription

Question 11

what is the promoter region of DNA?

Answer 11

transcription factor and RNA polymerase binding site

Question 12

what is the open reading frame?

Answer 12

AA encoding region containing introns and exons

Question 13

what is the UTR?

Answer 13

untranslated regions necessary for RNA processing

Question 14

RNA polymerase I

Answer 14

synthesizes ribosomal RNA or rRNA

Question 15

RNA polymerase II

Answer 15

synthesis messenger RNA or mRNA

Question 16

RNA polymerase III

Answer 16

synthesis of transfer RNA tRNA

Question 17

how is DNA read by the RNA polymerase?

Answer 17

read 3’-5’

made 5’-3’ (same as non template DNA)

Question 18

what initiates DNA binding of RNA polymerase?

Answer 18

transcription factor complexes

Question 19

Negative regulation of DNA transcription

Answer 19

• molecular signal causes repressor to move from operator region
• molecular signal binds with free repressor which then binds to operator region to inhibit transcription

Question 20

positive regulation of DNA transcription

Answer 20

• enhancement can occur with the removal of an activator(allow binding of RNA polymerase)
• or the binding of an activator(stabilize RNA polymerase)

Question 21

what are the Three RNA processing steps?

Answer 21

addition of 5’ cap
intron splicing
addition of poly A tail
**this is in order of how this happens

Question 22

what is the purpose of the 5’ cap?

Answer 22

• protects mRNA
• binds to ribosomes to initiate transcription
• tethers mRNA until translation is complete

Question 23

mRNA splicing

Answer 23

• four classes of introns
• two are self splicing
• most introns are not self splicing and require a spliceosomes.
• introns are released into nuclear space and degraded

Question 24

how does splicing lead to more protein diversity?

Answer 24

because splicing happens at different places depending on where it is produced
-thus 1 gene=more than one protein

Question 25

Termination and Poly A tail

Answer 25

``` AAUAAA upstream sequence G and U rich residues downstream protects mRNA tail Anchors mRNA during translation **occurs independent of RNA polymerase ```

Question 26

how does mRNA get out of the nucleus?

Answer 26

binding of protein factors bring the mRNA to nuclear pore and then go off to translation

Question 27

where are the two domains of translation

Answer 27

in the cytosol | and in RER membrane

Question 28

what is the importance of inosinate?

Answer 28

it is very promiscuous and allows for variance in the 3rd codon and allows for resistance to mutation.

Question 29

what are the five steps in translation?

Answer 29

``` activation of AAs initiation elongation termination protein folding ```

Question 30

what occurs in activation

Answer 30

aminoacylating tRNAs (putting the AA on the tRNA)

Question 31

what occurs in initiation

Answer 31

- initiation factors bind to 5' - recruit 40s ribosome complex, which scans mRNA for start codon and the anticodon binds. - poly A tail and 5' keep mRNA in place - then the large 60s ribosome binds * *ATP/GTP hydrolysis drives initiation

Question 32

elongation at the ribosome

Answer 32

- mRNA is read 5'-3' (opposite of RNA polym) - aminoacyl, peptidyl, and exit sites of large ribosome subunit (APE) - poly pep chain is made N->C terminus

Question 33

termination

Answer 33

termination factor causes release

Question 34

proteins made at the endoplasmic reticulum are what kind?

Answer 34

integral membrane proteins intravesicular proteins secreted proteins -primary site of protein modification

Question 35

what is the Signal Recognition Particle cycle?

Answer 35

the SRP on the ER causes the ribosome to associate and make the protein into that site at the RER. -GTP dependent

Question 36

post-translational modifications that occur within the ER

Answer 36

``` protein folding proteolytic cleavage -glycosylation -acetylation -phosphorylation -methylation -acylation ```

Question 37

proteins made at the ER are what kind. (3) of them

Answer 37

integral membrane proteins intravesicular proteins secreted proteins

Question 38

proteins made in the cytoplasmic space are what kind (3) types

Answer 38

nuclear proteins structurally associated proteins membrane-associated proteins

Question 39

how do proteins get into the nucleus?

Answer 39

because they have a nuclear localization sequence on them that recruits other proteins that bring that protein into the nucleus

Question 40

what targets a protein for degradation?

Answer 40

polyubiquitination tags a protein for destruction

Question 41

proteosome degrade what kind of proteins?

Answer 41

degrades cytoplasmic proteins

Question 42

lysosomes degrade what kind of proteins?

Answer 42

degrades vesicular and membrane proteins | *proteins made in the ER