Briefly explain how the leading and lagging strands of DNA are synthesized during DNA replication
Assignment 3 covers Module 5. The assignment is out of 100 marks and is worth 12.5% of the
final grade. The number of marks assigned for each question appears in parentheses following the question.
Note:
Remember to post your response to the discussion before you send Assignment 3 to your Open Learning Faculty Member for grading. Indicate in your assignment the date(s) you posted your contributions to the discussion. Refer to the instructions posted in the Discussions area for guidelines on participating.
Briefly explain how the leading and lagging strands of DNA are synthesized during DNA replication. (10 marks)
What is the function of each of the following? (2 marks each, 10 marks total)
Primase
Helicase
Nucleases
Histones
Poly(A) tail
What would be the complementary strand of the following portion of DNA: 3’AACCGTAATTCG5’? (3 marks)
Do one of the following. Define the following types of mutations: silent, nonsense, missense, and frameshift mutation, or answer the following: Using the following mRNA sequence, give an example of each type of mutation. (12 marks)
AUG GUG CCA UUC AAU AUG UGG
Summarize how a mature mRNA is made from the primary mRNA transcript. (6 marks)
Answer the following two questions: (8 marks total)
Describe the central dogma of molecular biology. (2 marks)
Give 3 reasons why proteins are not made directly from DNA. (Hint: Consider disadvantages of using DNA directly and/or advantages of not using DNA directly). (6 marks)
Compare and contrast the following which are involved in transcription: (4 marks each, 12 marks total )
Promoter proximal elements and promoter
Enhancers and silencers
Regulatory Transcription factors and co-activators
How can one gene code for more than one protein? (3 marks)
Describe levels of chromatin structure and explain how chromatin is decondensed to allow transcription. (10 marks)
Use the techniques in Chapter 7 of A Short Guide to Writing about Biology (introduced in Module 2, Topic 5) to write a one-paragraph summary of the Figure 15.2 Experiment “What do genes do?” in your textbook. Your summary should clearly state the goal and the key findings of the research performed in your own words. (8 marks)
Compare and contrast Dideoxy DNA sequencing and Southern Blotting with respect to procedure and purpose. (8 marks)
