DNA/RNA Answers

 1)  assimilation of external DNA into a cell

 2) 12

 3)  the relative proportion of each of the four bases differs from species to species.  the amount of A is always equivalent to T, and C to G.

 4)  purines; pyrimidines 

 5) hydrogen 

 6)  sequence of bases.

 7)  the 5' to 3' direction of one strand runs counter to the 5' to 3' direction of the other strand.

 8)  DNA polymerase

 9)  the nucleotide sequence of the template strand

 10)  to add nucleotides to the end of a growing DNA strand

 11)  d

12)  a

 13)  c

 14) e 

 15) b 

 16)  join Okazaki fragments together

 17)  initiating a polynucleotide strand.

 18) proofreading during DNA replication mismatch repair excision repair complementary base pairing during DNA replication

 19)  the two ends of a shoelace

 20) DNA is double-stranded, whereas RNA is single-stranded.

 21)  each new DNA double helix consists of one old DNA strand and one new DNA strand.

 22) DNA polymerase can assemble DNA only in the 5' to 3' direction 

 23) an RNA primer.

 24)  experience a gradual reduction of chromosome length with each replication cycle.

 25) nucleotides consisting of a phosphate, sugar, and nitrogenous base

 26)  ATP, RNA, and DNA 

 27) RNA acts as an expendable copy of the genetic material, allowing the DNA to serve as a permanent, pristine repository of the genetic material. many mRNA molecules can be transcribed from a single gene, increasing the potential rate of gene expression. 

 28)  ACU. 

 29)  900

 30) may code for the same amino acid as another codon.

 31) proline.

 32)  3' to 5'; 3' 

 33) An enzyme made up of RNA

 34) exons 

 35) excision of introns.

 36) UUU.

 37) bonding of the anticodon to the codon. attachment of amino acids to tRNAs. 

 38) tRNA

 39)  hydrogen bonding between base pairs

 40) some tRNAs have anticodons that recognize two or more different codons. the rules for base pairing between the third base of a codon and tRNA are flexible.

 41)  both rRNA and protein

 42) rRNA

 43) 

4, 1, 2, 5, 3

 44)  ligase

 45) small ribosomal subunit large ribosomal subunit initiator tRNA

 46)  A stop codon is encountered.

 47) A tRNA with the next amino acid enters the P site.

 48)  groups of ribosomes reading a single mRNA simultaneously

 49) point mutation

 50) point 

 51) base deletion near the start of a gene 

 52) GTTACG with CAAUGC

 53) the cytoplasm. 

 54) aminoacyl-tRNA synthetase

 55)  complementary to the corresponding mRNA codon.

 56) DNA

 57)  replication fork.

 58)  relieving strain in the DNA ahead of the replication fork