DNA vs. RNA Flashcards
sugar (DNA vs. RNA)
DNA: deoxyribose
RNA: ribose
types of nitrogenous bases (DNA vs. RNA)
DNA: A, T, C, G
RNA: A, U, C, G
number of nitrogenous bases (DNA vs. RNA)
DNA: avg 10^8 base pairs
RNA: 70-10,000 bases, mostly unpaired
number of nucleotide chains (DNA vs. RNA)
DNA: 2 (double helix)
RNA: 1
site of action (DNA vs. RNA)
DNA: functions in nucleus, cannot leave
RNA: leaves nucleus, functions mainly in cytoplasm
function (DNA vs. RNA)
DNA: codes for synthesis of RNA and protein
RNA: carries out the instructions in DNA; assembles proteins
a 3-base sequence of mRNA is called a ___
codon
which term refers to a sequence of 3 DNA nucleotides that codes for 1 amino acid?
base triplet
what is an essential function of RNA?
to use the instructions coded in DNA to synthesize proteins
DNA molecules tend to be much ___ than molecules of RNA
larger
where does the making of mRNA from DNA take place?
in the nucleus
the step from DNA to mRNA is called ___
transcription
the step from mRNA to protein is called ___
translation
transcription occurs in the ___, where ___ is
nucleus
DNA
most translation occurs in the ___ but can also occur in the ___
cytoplasm
nucleus
each amino acid is coded for by a ___, a sequence of ___ DNA nucleotides
base triplet
3
which enzyme is responsible for transcribing DNA?
RNA polymerase
which statement best summarizes the role of DNA in protein synthesis?
DNA contains the genetic doe that determines the Aino acid sequences of proteins
which term refers to the conversion of nucleotide sequences into amino acid sequences?
translation
which term refers to a sequence of 3 DNA nucleotides that codes for 1 amino acid?
a ___ is a 3-base sequence in mRNA
an ___ is a 3-base sequence in tRNA
base triplet
codon
anticodon
transcription is the process of typing genetic instructions from a molecule of ___ to mRNA
DNA
which molecule carries the genetic doe from the nucleus to the cytoplasm?
mRNA
the enzyme RNA polymerase participates in which of the following processes?
transcription
the process of reading an mRNA molecule and synthesizing the protein encoded in its nucleotide sequence is known as ___
translation
order of translation
1) ribosome binds mRNA
2) a tRNA anticodon binds to a complementary mRNA codon
3) a new amino acid is linked to the growing peptide chain
4) the tRNA is released from the ribosome and is now available to pick up another amino acid
since there are no genes coding for carbohydrates, nucleic acids, or lipids, how do cells produce them?
genes encode enzymes that synthesize these products
what is the role of mRNA in protein synthesis?
it carries the genetic code from the nucleus to the cytoplasm
what is the role of DNA in protein synthesis?
it stays w/in the nucleus and serves as the template for transcription
what is the role of RNA polymerase in protein synthesis?
it opens the DNA helix and reads the base from 1 strand of DNA
what is the role of tRNA in protein synthesis?
it binds free amino acids and delivers them to the ribosome to be added to a growing protein chain
anticodons are found on which type of molecule?
tRNA
___ are the cell structures that process coded genetic messages and assemble amino acids into proteins
ribosomes
genes mostly only synthesize ___
proteins
digestive enzymes are ___
secreted by exocytosis
sodium-potassium pumps are ___
delivered to the plasma membrane
kinases, ATPases are ___
used in the cytosol as metabolic enzymes
histones, RNA polymerase are ___
returned to the nucleus for cellular metabolism
there are no genes for glycogen, fat, steroids, phospholipids, and many other compounds, yet their synthesis is under indirect genetic control
these cell products are produced by enzymatic reactions, and enzymes are proteins encoded by genes
