Essay on Genetics: Dna and Dna Molecule

Submitted By bpwilla75
Words: 647
Pages: 3


1. A typical prokaryotic cell contains __________chromosome(s).

2. The basic building block of a DNA molecule is the__________________________

3. The observable physical traits of an organism are collectively referred to as its ______________________

4. An organism's genetic makeup is its_____________________________

5. The nitrogenous bases found in DNA are ____________, ______________,_____________and ______________.

6. In a DNA molecule thymine is always paired with ______________and guanine is always paired with ____________________. In RNA molecules thymine is replaced by __________________.

7. When DNA molecules are replicated, each strand serves as a(n)_____________________for the synthesis of the other.

8. The points at which the two DNA strands separate to allow replication of DNA on a prokaryotic chromosome are known as _______________________.

9. The enzyme ____________________moves behind replication forks, synthesizing new DNA strands complementary to the parent strands.

10. New DNA molecules contain one half old material and one half new. Their synthesis is therefore called ____________________________replication.

11. The three forms of RNA are ______________, __________________, and __________________.

12. The smallest of the RNA molecules is _________________, each of which transports a single type of ___________________for protein synthesis.

13. _________molecules combine with specific amino acids and bring them to the _____________during translation.

14. The genes of prokaryotes do not contain____________________, whereas those of eukaryotes almost always do. When these noncoding regions are removed from the precursor mRNA, the remaining ________________form the mature or final mRNA molecule.

15. In the overall protein synthesis process the formation of mRNA from a DNA template is called _______________.

16. The synthesis of a protein molecule from information in mRNA is called__________________.

17. A___________is one set of three nucleotides on mRNA that codes for a particular amino acid. A(n)

____________ is the complementary set of nucleotides on tRNA.

18. In eukaryotes, transcription takes place in the _____________________, and translation generally occurs in the __________________.

19. The initiator codon is _______and codes for the amino acid_____________________.

20. The last codon in a mRNA molecule that specifies the end of a protein molecule is known as a ____________codon.

21. Enzymes that are always produced by the cell under all conditions are called____________________

22. Enzymes that are produced only when certain conditions exist are called ___________________.

23. A permanent change in a DNA molecule is called a ________________.

24. A __________________mutation affects a single nitrogenous base, and a ______________mutation can affect more than one base in DNA.

26. The substitution of one nitrogenous base for another at a specific location in a gene occurs in a __________mutation. Three types of point mutations are ___________, ______ __________, ______________.

26. In frameshift mutation there is either a ______________________or a(n) ____________________of one or more bases.

27. Wild-type strains that often have the ability to grow on a