DNA AND RNA EXERCISE

 

 

 

1.   What are 4 differences between DNA & RNA? (Use a chart form)

 

 

 

2.   Define Transcription?  Where does it occur?

 

 

 

3.   Define Translation?  Where does it occur?

 

 

 

4.   How many hydrogen bonds are between each nitrogen base pairs? A – T & G – C.

 

 

 

5.   Define a nucleoside, a nucleotide, and a nucleic acid?

 

 

 

6.   What are codons and an anit-codons?

 

 

 

7.   What is the complementary DNA strand of ATTGCGGAAC?

 

 

 

8.   What is the complementary RNA strand of ATTGCGGAAC?

 

 

 

9.   What is DNA polymerase?

 

 

 

10. Why does DNA have a double helix shape?

 

 

 

11. What are the bonds between amino acids?  What is a polypeptide chain?

 

 

 

12. What are start (initiators) and stop (terminators) codons?

 

 

 

13. What is the function of tRNAs?  The amino acid binds to which part of the tRNA?       Which part of the tRNA binds to the mRNA template?

 

 

 

14. Explain the entire process of Protein synthesis to a friend.

 

 

 

 

 

 

 

Answers to DNA and RNA exercise

 

1.

DNA	RNA
Deoxyribose sugar	ribose sugar
double helix	single strand
nucleus	cytoplasm
thymine	uracil

 

 

2.   Transcription:  is the process in which the genetic code is copied from the DNA molecule to the mRNA (messenger RNA) molecule.  It occurs in the nucleus.

 

3.   Translation:  is the process in which proteins are made using the DNA instructions from the mRNA.  It occurs in the cytoplasm with the help of ribosomes.

 

4.   There are two hydrogen bonds between A & T and three between G & C.

 

5.   nucleoside:  a nitrogen base + a sugar

      nucleotide:  a nitrogen base + a sugar + a phosphate

      nucleic acid:  a lot of nucleotides

 

6.   Codons are three base codes for amino acids.  Anti-codons are also three base codes found on tRNAs which pair with codons.

 

7.   TAACGCCTTC.

 

8.   UAACGCCUUC.

 

9.   DNA polymerase in an enzyme that assists in protein synthesis.

 

10. DNA has a double helix shape because of the difference in the number of hydrogen bonds between the nitrogen bases.         

 

11. The bond between amino acids are called a peptide bond.  A polypeptide chain is a long chain of amino acids or a protein.

 

12. These are codons that do not code for amino acids.  Start codons initiate protein synthesis and stop codons terminate protein synthesis.

 

13. tRNAs are responsible for a major part of translation.  They go around the cytoplasm and collect amino acids.  The amino acids are brought to the ribosomes and are transferred over to the polypeptide chain.  The amino acids attach to the amino site of the tRNA.  The tRNA binds to the mRNA template by it’s anti-codon.