Lesson Plan

DNA Replication

Students will learn the steps of DNA replication
Alyssa C.
Classroom teacher
San Gabriel Academy
San Gabriel, CA
Show More
My Grades 9, 10, 11, 12
My Subjects Science
Objectives

Students will be able to

  • identify the three main steps of DNA replication
  • understand replication terms
    • helicase, polymerase, primase, Okazaki fragments, and ligase
  • differentiate between the leading and lagging strands
Subjects
Science
Grades 9 - 10
All Notes
Teacher Notes
Student Notes

1 Engage

Nearpod
Free, Paid
  • Nearpod quiz
    • What does DNA stand for?
    • What is DNA composed of?
    • What is the proper base pairing in DNA?
    • What is antiparallel?

2 Explore

  • Play the TED talk video for 12 minutes
  • After the video, begin discussion questions
    • What are the student's opinions about being able to edit our own DNA?
      • Are there any moral implications?
    • What are the benefits and consequences to using CRISPR?
    • How does editing our DNA relate to Darwin's theory of evolution, or from a creationist's perspective, intelligent design?
    • If we could edit out mutations, what would the world look like with a seemingly perfect human race?

 

Student Instructions
  • Discuss the TED talk video with the class
  • Answer discussion questions provided by the teacher

3 Explain

  • Explain the key components of DNA replication
    • Provide the vocabulary blanks for the notes
    • Draw DNA replication with the students
      • Drawing helps students visualize and connect each step

 

Teacher and Student notes

Chapter 12 Section 2 Replication of DNA

  1. During _________________________ _________________________, parental strands of DNA separate, serve as templates, and produce DNA molecules
    1. Each DNA molecule has _________________________ parental strand and one template strand
    2. Replication occurs during _________________________ of mitosis and meiosis
    3. Semiconservative replication occurs in three main stages:

i._________________________

ii._________________________ pairing

iii._________________________

  1. Unwinding
    1. An enzyme called DNA _________________________ is unwinds (_________________________) the double helix

i.Unwinding breaks the _________________________ bonds between the nucleotide bases

  1. Proteins called _________________________-_________________________ binding proteins keep the strands separated
  2. As the helix unwinds, _________________________ primase adds RNA primers to each DNA strand
  1. Base pairing
    1. An enzyme called DNA _________________________ adds nucleotides to the new DNA strand
    2. Nucleotides are added to the _________________________ end of the new strand
    3. Each strand is made in a different manner

i.One strand is called the _________________________ strand and is elongated towards the _________________________ fork

  1. Strand is made _________________________

ii.The other strand of DNA is called the _________________________ strand and it elongates away from the replication fork

  1. The lagging strand is synthesized into smaller segments called _________________________ _________________________
    1. Synthesized by DNA polymerase in the _________________________ direction
    2. Fragments are later connected by the enzyme called DNA _________________________
  1. Joining
    1. When DNA _________________________ encounters an RNA _________________________, it removes the primer and fills it with nucleotides
    2. DNA _________________________ then connects the fragments

 

 

 

Chapter 12 Section 2 Replication of DNA TEACHER NOTES

  1. During ____semiconservative____ _____replication____, parental strands of DNA separate, serve as templates, and produce DNA molecules
    1. Each DNA molecule has ___one___ parental strand and one template strand
    2. Replication occurs during ___interphase__ of mitosis and meiosis
    3. Semiconservative replication occurs in three main stages:

i._____

ii._____ pairing

iii._____

  1. Unwinding
    1. An enzyme called DNA __helicase___ is unwinds (__unzips__) the double helix

i.Unwinding breaks the ____ bonds between the nucleotide bases

  1. Proteins called ___single___-____stranded__ binding proteins keep the strands separated
  2. As the helix unwinds, __RNA__ primase adds RNA primers to each DNA strand
  1. Base pairing
    1. An enzyme called DNA __polymerase__ adds nucleotides to the new DNA strand
    2. Nucleotides are added to the ___3’___ end of the new strand
    3. Each strand is made in a different manner

i.One strand is called the ____ strand and is elongated towards the ___ fork

  1. Strand is made __continuously___

ii.The other strand of DNA is called the ____ strand and it elongates away from the replication fork

  1. The lagging strand is synthesized into smaller segments called ___Okazaki___ ___fragments___
    1. Synthesized by DNA polymerase in the __3’ to 5’__ direction
    2. Fragments are later connected by the enzyme called DNA __ligase___
  1. Joining
    1. When DNA __ligase__ encounters an RNA __primer__, it removes the primer and fills it with nucleotides
    2. DNA __ligase__ then connects the fragments

 

 

 

Student Instructions
  • Follow the ShowMe presentation
  • Draw DNA replication

4 Elaborate

Activity: Other — Act out DNA replication (or use other evaluation methods listed below if class prefers not to act)

There will be MINIMAL to NO teacher input in this section

  • Students are to work and collaborate together to demonstrate their understanding of DNA replication
    • Students are to put away all notes and resources
  • Assign students roles in DNA replication
    • One student for DNA ligase, DNA polymerase, and RNA primase
    • The rest of the class will be the DNA backbone and nucleotide bases
  • DEPENDING ON HOW THE STUDENTS LEARN, if they are not comfortable with acting out the steps, they may be divided into two groups and compete with each other to draw each step
  • ANOTHER POSSIBLE EVALUATION may be to divide students into six groups and have them present to the class each component of replication
 

The groups are: helicase, polymerase, primase, ligase, leading strand, and lagging strand

5 Evaluate

Nearpod
Free, Paid
  • Nearpod quiz
    • What enzyme unzips the DNA double helix?
    • What prevents the DNA strands from sticking together after unwinding?
    • Which strand replicates towards the replication fork?
    • What is the purpose of the DNA polymerase?
    • What enzyme joins the DNA strands after replication?
Student Instructions
  • Complete the Nearpod quiz