DNA Replication Worksheet #1 PDF

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Summary

This is lab 3 from the maternity unit. There are 2 pages...

Description

Name: Maurio Goings

1. Why does DNA need to replicate?

2. In relation to the pictures below: Explain three main steps in the process of DNA replication. Name the enzymes that go with each step. a. Initiation -

DNA becomes more accessible to proteins and enzymes during the replication process. The enzyme, helicase, unwinds the double helix of DNA in a process of breaking hydrogens bonds between the base pairs

b. Elongation -

The complimentary strands are now in the process of becoming synthesis. DNA polymerase III, an enzyme, controls elongation and adds 5’ to 3’ nucleotides

c. Termin ation -

It is important to note in this step that the last primer in the double helices sequence must be removed. The enzyme nuclease are essentially the last check before the structure come together and check for mispairs.

3. In which direction are new nucleotides added during replication? -

5’ to 3’

4. What is the difference between and leading and lagging strand? -

Leading strand (New strand of DNA that is continuous) is synthesized in the 5’ to 3’ and lagging strands (New fragments that grow from Okazaki fragments) are synthesized to the 3’-5’

5. Which enzyme is responsible for “unzipping” the DNA double helix? - Helicase 6. Which enzyme is responsible for facilitating the hydrogen bonding between nucleotides in a new DNA molecule? - DNA polymers 7. Which enzyme is responsible for creating the covalent bonds (specifically phosphodiester bonds) that connect the sugar-phosphate backbone of the new DNA molecules? - Ligase 8. Below is a single strand of DNA. Below each letter write the complementary strand of DNA. A –T–G–C–G–G–C–G–A –T–T–T–A –A –G–C T-A-C-G-C-C-G-C-T-A-A-A-T-T-C-G 9. a. In the box A below, fill in the complementary strand of DNA to create a double strand. b. Next to the box, using two different colored pens/pencil, create two new strands from the original strand in the box A. Label which color represents the original strand and which color represents the new strand. Box A: A T

T A

G G

C C

C T

G A

A G

T C

Part T A C C G A T C

b: A T G G C T A G

A T G G C T A G

T A C C G A T C

10. Describe the origin of each strand of the new double helices created after DNA replication.

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The newly un-winded double helix represents itself as a template for the new strands

11. Why do you think DNA replication important to the growth and development of a multi-cellular organism?

-

The new daughter cells are copies of the parent DNA strands in growth/repair

12. What do you think would happen if the process occurred incorrectly? -

The DNA would replicate in a wrong way and create mutations...