Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
99 Cards in this Set
- Front
- Back
|
Photorespiration is an apparently wasteful process in plants that results from ____ of Rubisco |
the oxygenase function |
|
|
the nucleotides in a messenger RNA that specify an amino acid in a protein are called |
a codon |
|
|
molecular machine that synthesizes proteins |
ribosomes |
|
|
____ contains the information prescribing the amino acid sequence of proteins |
DNA |
|
|
the entire nucleic acid sequence that is necessary for the synthesis of a functional gene product |
gene |
|
|
____ serves in the cellular machinery that chooses and links amino acids in the correct sequence |
RNA |
|
|
The end of a protein where protein synthesis starts |
amino terminus (N-terminus) |
|
|
The end of protein where protein synthesis ends |
c-terminus |
|
|
_____ make peptide bonds between amino acids. |
ribosomes |
|
|
Protein synthesis starts at the ___ end and ends at the ___ end. |
5' and 3' |
|
|
A template DNA strand is transcribed into a complementary RNA chain by __________. |
RNA polymerase |
|
|
General structure of a eukaryotic mRNA |
cap structure-->5' UTR-->AUG initiation codon--> Protein coding region (ORF-open reading frame)-->Termination codon-->3' UTR--> Poly (A) tail |
|
|
the _____ is added post transcription |
poly A tail |
|
|
carries information copied in the form of a series of three base "words" termed codons |
messenger RNA (mRNA) |
|
|
deciphers the code and delivers the specified amino acid |
Transfer RNA (tRNA) |
|
|
activate amino acids by covalently linking them to tRNAs |
Aminoacyl-tRNA synthetases |
|
|
associates with a set of proteins to form ribosomes, structures that function as protein-synthesizing machines |
ribosomal RNA (rRNA) |
|
|
amino acids become activated when covalently linked to ______ |
tRNAs |
|
|
start codon in RNA |
AUG |
|
|
start codon in DNA |
ATG |
|
|
prokaryotic ribosomal subunits |
50S and 30S |
|
|
eukaryotic ribosomal subunits |
60S and 40S |
|
|
density of assembled prokaryotic ribosome |
70S |
|
|
density of assembled eukaryotic ribosome |
80S |
|
|
3 stages of protein synthesis |
initiation-->elongation-->termination |
|
|
_____ recognizes the AUG start codon |
methionyl-tRNA |
|
|
_____ must happen to power initiation |
GTP hydrolysis |
|
|
During chain elongation, each incoming aminoacyl-tRNA moves through ___ ribosomal sites. |
3 |
|
|
Translation is terminated by ______ when a stop codon is reached. |
release factors |
|
|
Polysomes and rapid recycling ____ the efficiency of translation. |
increase |
|
|
The ________ structure of mRNA increases translational efficiency. |
circular |
|
|
Transport Across ER Membrane _____ terminus comes out of the ribosome first |
amino |
|
|
Transport Across ER Membrane protein synthesis begins at the _____ terminus |
amino |
|
|
Transport Across ER Membrane translation and translocation occur _______ |
simultaneously |
|
|
Transport Across ER Membrane Cotranslational translocation is initiation by two ________________ proteins |
GTP-hydrolyzing |
|
|
Transport Across ER Membrane protein is being synthesized as it crosses ER membrane |
cotranslational translocation |
|
|
Transport Across ER Membrane receptor for N-terminus for protein being synthesized |
signal-recognition particle (SRP) |
|
|
Transport Across ER Membrane Cotranslational translocation Steps |
1. Ribosome with protein binds to SRP receptor 2. Translocon closed. GTP binds to SRP receptor. 3. Translocon opens. 4. Signal peptidase cleaves signal sequence. 5. Protein enters ER and folds. |
|
|
Transport Across ER Membrane recognizes the point where the signal sequence stops and target protein starts and cleaves at that point |
signal peptidase |
|
|
Transport Across ER Membrane Passage of growing polypeptides through translocon is driven by energy released during __________ |
translation |
|
|
Transport Across ER Membrane _______ powers post-translational translocation of some secretory proteins in yeast; very few proteins use this pathway; most use cotranslational translocation |
ATP hydrolysis |
|
|
Transport Across ER Membrane In post-translational translocation, _____ helps fold proteins. |
HSC70 also known as BiP |
|
|
Transport Across ER Membrane Post-translational translocation is dependent on _________. |
ATP hydrolysis |
|
|
Transport Across ER Membrane There is no ______ in post-translational translocation. |
SRP receptor |
|
|
Transport Across ER Membrane stops protein being pushed through translocon |
stop transfer anchor sequence |
|
|
Transport Across ER Membrane ER membrane proteins that are single-pass |
Type I, II, III and tail anchored proteins
|
|
|
Transport Across ER Membrane ER membrane proteins that are multi-pass |
Type IV proteins with N-terminus in cytosol Type IV proteins with N-terminus in exoplasmic space |
|
|
Transport Across ER Membrane A ________ anchor tethers some cell-surface proteins to the membrane. |
phospholipid |
|
|
Transport Across ER Membrane _______ side chains may promote folding and stability of glycoproteins |
oligosaccharide |
|
|
Transport Across ER Membrane ________ are formed and rearranged by proteins in the ER lumen |
Disulfide bonds |
|
|
Transport Across ER Membrane amino acid that leads to disulfide bond formation |
cysteine |
|
|
Transport Across ER Membrane _____ facilitate folding and assembly of proteins |
chaperones |
|
|
Transport Across ER Membrane Calcium dependent chaperones that help fold protein hemagglutinin |
calreticulin and calnexin |
|
|
Transport Across ER Membrane enzyme in lumen of ER that catalyzes isomerization |
peptidyl prolyl isomerase (PPI) |
|
|
Transport Across ER Membrane When monitoring protein folding, EDEM and OS-9 triggers ________. |
Degradation |
|
|
Transport Across ER Membrane When monitoring protein folding, CNX/CRT triggers _______. |
Folding/retention |
|
|
The location of sequence within protein for endoplasmic reticulum is located at the ________. |
N-terminus |
|
|
For endoplasmic reticulum transport of proteins, the sequence is removed. True or False? |
True |
|
|
Transport Across Mitochondria Location of sequence within protein is at ________. |
N-terminus |
|
|
Transport Across Mitochondria The sequence is removed. True or False? |
True |
|
|
Transport Across Mitochondria Amphipathic N-terminal signal sequences direct proteins to the ______________. |
mitochondrial matrix |
|
|
Transport Across Mitochondria Mitochondrial protein import requires __________ and ______ in both membranes. |
outer-membrane receptors and translocons |
|
|
Transport Across Mitochondria Three energy inputs that are needed to import proteins into mitochondria |
ATP hydrolysis by cystolic Hsc70 ATP hydrolysis by matrix Hsc70 Proton motive force |
|
|
Transport Across Chloroplasts Location of sequence within protein is at the __________. |
N-terminus |
|
|
Transport Across Chloroplasts The sequence is removed. True or False? |
True |
|
|
Transport Across Chloroplasts Proteins are targeted to _______ by mechanisms related to translocation across the bacterial inner membrane. |
thylakoids |
|
|
Transport Across Peroxisomes Location of sequence within protein is at the __________. |
C-terminus |
|
|
Transport Across Peroxisomes The sequence is removed. True or False?
|
False |
|
|
Transport Across Peroxisomes A cytosolic receptor targets proteins with an _________ at the C-terminus into the peroxisomal matrix. |
SKL sequence |
|
|
Transport Across Peroxisomes _____ is on the membrane and ______ is inside the peroxisome |
PMP70 and catalase |
|
|
Transport Across Peroxisomes disease where peroxisomes don't form properly |
Zellweger syndrome |
|
|
Transport Across Peroxisomes Pex12 mutants lack _______ in cells, which is important in moving proteins into peroxisome. |
catalase |
|
|
Transport Across Peroxisomes _____ mutants don't form normal peroxisomes at all. |
Pex3 |
|
|
Transport Across Nucleus Large and small molecules enter and leave the nucleus via _____________________. |
nuclear pore complexes |
|
|
Transport Across Nucleus Nuclear transport receptor that excorts proteins containing nuclear localization signals into the nucleus. |
importins |
|
|
Transport Across Nucleus Location of sequence within protein is at the __________.
|
Varies |
|
|
Transport Across Nucleus The sequence is removed. True or False? |
Fasle |
|
|
Transport Across Nucleus detergent that pokes holes in plasma membrane and leaks out cytoplasm |
digitonin |
|
|
Transport Across Nucleus A second type of nuclear transport that transports proteins containing nuclear export signals out of the nucleus. |
exportins |
|
|
Transport Across Nucleus Most mRNAs are exported from the nucleus by a RAN-__________ mechanism. |
independent |
|
|
Transport from rough ER--> golgi |
anterograde |
|
|
transport from Golgi--> Rough ER |
Retrograde |
|
|
Cisternal maturation |
cis-->medial-->trans |
|
|
assembly of a __________ drives vesicle formation and selection of cargo vesicles |
protein coat |
|
|
______ assists in transport from Er--> cis golgi |
COPII |
|
|
______ assists in transport from cis-Golgi- ER |
COPI |
|
|
GTPase switch that controls COPII |
Sar1 |
|
|
GTPase switch that controls COPI and clathrin and adapter proteins |
ARF |
|
|
Signal sequence associated with COPII |
Diacidic (Asp-X-Glu) |
|
|
signal sequence associated with COPI |
Lys-Asp-Glu-Leu (KDEL) |
|
|
Anterograde transport through the Golgi occurs by ____________. |
cisternal maturation |
|
|
Vesicles coated with _______ and/or _______ mediate transport from the trans-Golgi. |
clathrin; adaptor proteins |
|
|
_______ is required for pinching off of clathrin vesicles |
Dynamin |
|
|
_________ residues target soluble proteins to lysosomes. |
Mannose 6-phosphate |
|
|
degrade many organelles, membranes, proteins that have outlived their usefulness |
lysosomes |
|
|
soluble macromolecules taken into cell by invagination of clathrin coated pits |
endocytosis |
|
|
whole cells and large insoluble particles taken into the cell |
phagocytosis |
|
|
worn out organelles and cytoplasm |
autophagy |
|
|
______ result from the fusion of a primary lysosome with other membranous organelles |
Secondary lysosomes |
