Biochem PART IV Flashcards
(16 cards)
QUESTION 65: What parts of a ribonucleotide may undergo chemical modifications in RNA molecules?
-What are the 3?
- Nitrogenous base
- Ribose sugar
- Phosphate group
QUESTION 66: What ypes of chemical modifications might disrupt a Watson-Crick base pair?
-What are the 4?
- Trancription
- Alkylation
- Deamination
- Oxidation
QUESTION 67: What tole does transfer RNA play in a cell?
-tRNA links what?
-What is this process called?
-It brings amino acids where? For what?
-mRNA and the chain of amino acids
-protein synthesis
-Ribosome; translation
QUESTION 68: To what does the term translation refer?
-It is the biological process where the genetic code in ____ is _____ to build a ____
-What is a protein?
-mRNA
-decoded
-protein
-a chain of amino acids
QUESTION 69: What is a ribosome?
-What is it responsible for?
-It binds to ____, matches ____ to ____, and forms _____ _____ between amino acids, creating ____
-protein synthesis
-mRNA; tRNA to mRNA, peptide bonds; proteins
QUESTION 70: What is the anticodon & where can it be found?
-An anticodon is a sequence of ___ ____ on ____ that ensures accurate ____ by pairing with the ____ on mRNA (__-__, __-__)
-3 nucleotides
-tRNA
-translation
-codon
-A-U, C-G
QUESTION 71: What features give rise to the L-shaped structure of transfer RNA?
-What are the 3?
- Anticodon loop in the middle of tRNA
- Acceptor stem
- Elbow
QUESTION 72: What is a noncanonical base pair? What role might it play in RNA?
-Noncanonical base pairs do not follow what?
-What do they allow for during translation?
-the standard Watson-Crick pairing
-flexibility in codon recognition
QUESTION 73: What are the chemical componenets of a ribosome?
-The ribosome is half _____ and half ____
-rRNA provides the ____ ____ & plays a role in ___ ___
-proteins; rRNA
-structural framework
-protein synthesis
QUESTION 74: How do the secondary structural elements of a ribosome differ from those of transfer RNA?
-tRNA folds into what kind of shape?
-Ribosome has a _____-_____ structure with what four things?
-Ribosomes are (shorter/longer) than tRNA
-Do ribosomes have canonical base pairs?
-cloverleaf shape with 4 loops
-stem-loop; stems, loops, bulges, and junctions
-longer
-No
QUESTION 75: In what ways does the human ribosome resemble and differ from that of the Escherichia coli ribosome?
-Both undergo what?
-They have ___ and ___ subunits
-They have an __-____ tRNA binding cleft
-translation
-large and small
-L-shaped
QUESTION 75: In what ways does the human ribosome resemble and differ from that of the Escherichia coli ribosome?
-The human ribosome is what size?
-Is it eukaryotic or prokaryotic?
-It hase (shorter/longer) rRNA
-Where are the expansion elements?
-80s
-eukaryotic
-longer
-on the exterior
QUESTION 75: In what ways does the human ribosome resemble and differ from that of the Escherichia coli ribosome?
-What is the size of E. coli ribosomes?
-They are eukaryotic or prokaryotic?
-They have (shorter/longer) rRNA
-Where are the expansion elements?
-70s
-prokaryotic
-shorter
-on the interior
QUESTION 76: How do proteins associate with RNA on the ribosome?
-The ____ of the ribosome is largely ___-___, with only a ____ proteins making contact witht the ____ at specific sites
-interior
-protein-free
-few
-tRNA
QUESTION 77: How does B-strand differ from an a-helix?
-B-strand is ___/___ structure. It has adjacent ____ that alternate ____ and ____
-a-helix is ____/____ structure. It has ____ ____ ____, forming solitary or bundled helices
-extended/zig zag
-strands; above and below
-coilde/spiral
-side groups outward
QUESTION 78: How does the assembly of B-strands into B-sheets differ from the assembly of a-helices in the nucleosome?
-B-strands assemble into B-sheets through what?
-a-helices are assemled from ____ ____ into an _____ ____ that contains what?
-hydrogen bonding between adjacent strands
-histone proteins
-octamer core; H2A, H2B, H3, H4
