Question

question: how does dna make a copy of itself?

1. observe: an enzyme is a protein that facilitates certain cell processes. drag the blue dna helicase enzyme onto the dna strand. what does this enzyme do to the dna molecule?
2. observe: drag the yellow dna polymerase molecule onto the dna strand. dna polymerase adds complementary nucleotides to create new double - stranded dna molecules. notice two groups of nucleotides on the right.

a. drag one of the nucleotides to a corresponding nitrogenous base on one of the two strands. what is the role of dna polymerase in this process?
b. continue adding nucleotides to both strands. what happens to the dna polymerase molecule each time you add a nucleotide?
c. complete the two dna molecules. how do these molecules compare to each other?

1. compare:

how are the \daughter dna molecules.\ molecules compared to the original?
congratulations! you have completed the process of replication, where one \parent\ dna strand divides form two identical \daughter\ dna strands.

1. think and discuss: why is dna replication such an important process?
2. extend your thinking: sometimes errors called mutations occur during dna replication. what are the possible consequences of mutations?

Explanation:

1. DNA helicase unwinds and separates the DNA double - helix.
2. A. DNA polymerase catalyzes the addition of nucleotides to form new DNA strands.

B. The DNA polymerase molecule moves along the strand as nucleotides are added.
C. The two DNA molecules are identical to each other.

1. Daughter DNA molecules are identical to the original.
2. DNA replication is important for cell division (so each new cell has a full set of genetic information), growth, and repair.
3. Mutations can lead to genetic disorders (e.g., sickle - cell anemia), can be beneficial (e.g., antibiotic resistance in bacteria), or have no effect (silent mutations).

Answer:

1. Unwinds and separates the DNA double - helix.
2. A. Catalyzes nucleotide addition for new strand formation.

B. Moves along the strand.
C. Identical to each other.

1. Identical to the original.
2. Essential for cell division, growth, and repair.
3. Can cause genetic disorders, be beneficial, or have no effect.