15.1 The Genetic Code
Protein sequences consist of ---- commonly occurring amino acids;
20
Transcription always proceeds from the same DNA strand for each gene, which is called the
HINT strand
template strand.
s. Eukaryotic mRNAs are usually ------ meaning that they specify a single protein.
monogenic,
Eukaryotic mRNAs last for several hours, whereas the typical E. coli mRNA lasts no more than--------
The synthesis of proteins consumes more of a ----------- than any other metabolic process.
cell’s energy
, the translation to protein is still systematic and ----
colinear,
The mRNA product is complementary to the template strand and is almost identical to the other DNA strand, called the
nontemplate strand
or coding strand
The features of eukaryotic mRNA synthesis are markedly more complex than those of -----.
prokaryotes
The cell performs an additional RNA processing step called ---------to remedy this
RNA editing
. A ------- is a complex macromolecule composed of structural and catalytic rRNAs, and many distinct polypeptides
ribosome
Each amino acid is defined by a three-nucleotide sequence called the
triplet codon
---- do not have membrane-enclosed nuclei.
Prokaryotes
. Transcription factors that bind to the promoter are called------- factors.
basal transcription
The tRNA folds to position the amino acid binding site at one end and the ---- at the other end
anticodon
. In -------, the nucleolus is completely specialized for the synthesis and assembly of rRNAs.
eukaryotes
The specification of a single amino acid by multiple similar codons is called
"degeneracy."
Four of these subunits, denoted α, α, β, and β', comprise the polymerase----
core enzyme.
Some eukaryotic promoters also have a conserved -----
CAAT box
. The anticodon is a ------- sequence in a tRNA that interacts with an mRNA codon through complementary base pairing.
three-nucleotide
. The complete mRNA/polyribosome structure is called a ------.
polysome
The genetic code is nearly---
universal
The polymerase comprised of all five subunits is called the -----
holoenzyme.
----- transcription is a tightly regulated process that requires a variety of proteins to interact with each other and with the DNA strand.
Eukaryotic
Pre-tRNAs are transcribed and processed in the nucleus and then released into the ------ where they are linked to free amino acids for protein synthesis.
cytoplasm
Through the process of tRNA “charging,” each tRNA molecule is linked to its correct amino acid by one of a group of enzymes called---------
aminoacyl tRNA synthetases.