Nucleic Acids and Protein Synthesis

What is the difference between the $3\text{'}$ end and the $5\text{'}$ end of a polynucleotide chain?

What components join together to form the backbone of a nucleic acid?

What component in the backbone of nucleic acid is bonded to a nitrogen base?

What component is a nucleic acid determines the $5\text{'}$ free end?

What component in a nucleic acid determines the $3\text{'}$ free end?

Draw the condensed structural formula for the dinucleotide $\mathrm{G} C$ that would be in $\mathrm{RNA}$.

Draw the condensed structural formula for the dinucleotide A $\mathrm{T}$ that would he in DNA.

Write the base sequence in a complementary DNA segment if each original segment has the following base sequence:

a. T T T T T T

b. CCCCCCCCC

c. ATGGCA

d. ATATGCGCTAAA

How many daughter strands are formed during the replication of DNA?

List three structural characteristics of $\mathrm{DNA}$.

How are the two strands of nucleic acid in $\mathrm{DNA}$ held together?

What is meant by double helix?

What is meant by complementary base pairing?

What is the function of the enzyme helicase in DNA replication?

What is the function of the enzyme DNA polymerase in DNA replication?

What process ensures that the replication of DNA produces identical copies?

Write the base sequence in a complementary DNA segment if each original segment has the following base sequence:

a. A A A A A A

b. GGGGGG

c. AGTCCAGGT

d. CTGTATACGTTA

What is the smallest RNA?

What is meant by the term "transcription"?

What bases in mRNA are used to complement the bases $A$, $T$, $\mathrm{G}$, and $\mathrm{C}$ in DNA?

Write the corresponding section of mRNA produced from the following section of DNA template strand:

$C C G A A G G T T C A C$

Write the corresponding section of mRNA produced from the following section of DNA template strand:

$T A C G G C A A G C T A$

What are the three different types of RNA?

What are the functions of each type of RNA?

What is the composition of a ribosome?

What is the difference between a codon and an anticodon?

The following sequence is a portion of the DNA template strand:

TGT GGG GTT ATT

a. Write the corresponding mRNA segment.

b. What are the anticodons of the tRNAs?

c. Write the three-letter and one-letter abbreviations for this segment in the peptide chain.

The following is a segment of the DNA template that codes for human insulin:

TTT GTG AAC CAA CAC CTG

a. Write the corresponding mRNA segment.

b. Write the three-letter and one-letter abbreviations for this corresponding peptide segment.

Why are there at least $20$ different tRNAs?

What are the three steps of translation?

Where does protein synthesis take place?

What is a codon?

The codons$\mathrm{UGA}, \mathrm{UAA}$, and $\mathrm{UAG}$ do not code for amino acids. What is their role as codons in $\mathrm{mRNA}$?

The following is a segment of the DNA template that codes for human insulin:

TGC GGCTCA CAC CTG GTG

a. Write the corresponding mRNA segment.

b. Write the three-letter and one-letter abbreviations for the corresponding peptide segment.

Use three-letter and one-letter abbreviations to write the amino acid sequence for the peptide from each of the following mRNA sequences:

a. $\mathrm{ACC} \mathrm{ACA} \mathrm{ACU}$

b. $UUU CCG UUC CCA$

c. $UAC GGG AGA UGU$

Use three-letter and one-letter abbreviations to write the amino acid sequence for the peptide from each of the following mRNA sequences:

a. $AAA CCC UUG GCC$

b. $CCU CGC AGC GGC UGA$

c. $AUG CAC AAG GAA GUA CUG$

How is a peptide chain extended?

What is meant by "translocation"??

The following sequence is a portion of the DNA template strand: $GCT ATA CCA AAA$

a. Write the corresponding mRNA segment.

b. What are the anticodons of the tRNAs?

c. Write the three-letter and one-letter abbreviations for this segment in the peptide chain.

What is a point mutation? 

How does a point mutation for an enzyme affect the order of amino acids in that protein?

What is the effect of a deletion mutation on the amino acid sequence of a polypeptide? 

How can a mutation decrease the activity of a protein? 

How is protein synthesis affected if the normal base sequence $CCC$ in the DNA template strand is changed to $ACC$? 

Consider the following segment in $mRNA$, which is produced by normal order of DNA nucleotides      $-ACA UCA CGG GUA-$

1. What is the amino acid order produced from the $mRNA$?
2. What is the amino acid order if a mutation changes $UCA$ to $ACA$?
3. What is the amino acid order if a mutation changes $CGG$ to $GGG$?
4. What is the amino acid order if a mutation changes $UCA$ to $UAA$?
5. What happens if a $G$ is added to the beginning of the $mRNA$ segment?
6. What happens if the $A$ is removed from the beginning of the $mRNA$segment? 

How is protein synthesis affected if the normal base sequence$TTT$ in the DNA template strand is changed to$TTC$?

a. A point mutation changes a codon in the mRNA for an enzyme from GCC to GCA. Why is there no change in the amino acid order in the protein?

b. In sickle-cell anemia, a point mutation in the mRNA for hemoglobin results in the replacement of glutamate with valine in the resulting hemoglobin molecule. Why does the replacement of one amino acid cause such a drastic change in biological function?

a. A point mutation in the mRNA for an enzyme results in the replacement of leucine with alanine in the resulting enzyme molecule. Why does this change in amino acids have little effect on the biological activity of the enzyme?

b. A point mutation in mRNA replaces cytosine in the codon UCA with adenine. How would this substitution affect the amino acid order in the protein?

Why are $E.$ coli bacteria used in recombinant DNA procedures? 

What is a plasmid?