1. 
A. Each strand unwinds and separates. An enzyme helicase initiates this process. 
          Result: DNA strands are separated and exposing their nitrogenous 
                     bases. These two strains are the parent DNA strands.l 

B. Complementary nucleotides will match up: "A" to "T" and "C" to "G". This is carried out in a 3' to 5' directions initiated by a DNA polymerase enzyme.  These nucleotides are present in the nucleus of a cell where they are synthesized or acquired by digestion of DNA in food substances and transported to the nucleus. 

         Result: Two double stranded DNA molecules formed and each double 
                    strand DNA molecules contains one parent DNA strand (original) 
                    and one daughter strand (newly synthesized strand). This is called 
                    semi conservative replication because one strand is one half of the 
                    parental DNA and the other strand is newly synthesized DNA. 
 

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2. 
B. One DNA strain remains while the other is newly synthesized.  The sequence of nucleotides in each newly formed strand is complementary to the sequence on a parental strand.  As a result, two double helices are synthesized, each consisting of one parental DNA strand plus one newly synthesized, complementary strand that is an exact copy of the other parental strand.  The two daughter DNA molecules are therefore duplicates of the parental DNA molecule. 
 

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3. 
A. connects backbones of newly synthesized polynucleotide. 
An enzyme called DNA ligase bonds the two strands together.  This process is repeated many times until the entire lagging strand has been replicated.  Because the end of the parental double helix, even the leading strand must be synthesized in several pieces and must also be stitched together by DNA ligase. 

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4. 
AATCATGGC 
TTAGTACCG 

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5. 

A. Segment of DNA in chromatin untwists and exposes it nitrogen bases. During replication the entire DNA is copied; however, during transcription small segments of DNA are copied in the form of RNA  segments. 
           (promoter and RNA polymerase) 
B. The difference between the DNA and newly synthesized RNA molecule are that the nucleotides which are attracted to the complementary bases  contain ribose sugar in place of deoxyribose and the base "U" is used in place of "T".. 

C. mRNA release from the parent DNA moves  to the cytoplasm by passing through the are nuclear pores. mRNA becomes associated with ribosome which consists of rRNA which acts as a stage where protein synthesis is going to occur.  The ribosome's are decomposed of protein and rRNA (ribosomal RNA). Ribosome's are synthesized in the nucleolus of the nucleus. 

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6. 
T T  T A A  T C A T  G G C    (DNA) 
A A A U U A G U A C C G    (mRNA) 

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7. 
mRNA 
A codon is a sequence of three bases of messenger RNA that specifies a particular amino acid to be incorporated into a protein.  Certain codons also signal the beginning and end of protein synthesis. 

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8. 
tRNA 
An anticodon is a sequence of three bases in transfer RNA that is complementary to the three bases of a codon of messenger RNA. 

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9. 
Three bases are present in a codon or anticodon. 

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10. 
UAC 
In eukaryotic cells the first step in translation is the binding of several protein "initiation factors" and a tRNA bearing the complementary "start anticodon" UAC to the small subunit of a ribosome.  At the point of the UAC anticodon on the initiator tRNA base pairs with the AUG of the start codon. 

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11. 
T A C C C T C A A G  A T G C G T T C 
A U G G G A G U U C U A C G C A A G 

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12. 
tRNA which have anticodon matching the specific amino acid. 
Examples: 
AAA with UUU and phenylalanine 
GUA with CAU and histidine 
CCC with GGG and Glycine 

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13. 
 T A C- C C T -C A A- G A T -T A A 
A U G -G G A -G U U- C U A-A U U 
(start)  -Glycine-Valine- Leucine-(stop) 

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14. 
AUG UAU AAA UUU UUC UGU GGU AAA 

There are many base sequences for the gene which form  the polypeptide. 

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15. 
Phenylalanine 

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16. 
Asparagine 

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17. 

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