ED Compendium for web

How do living things pass traits to their offspring?

Learning Targets

Learning Experiences

Learning Targets

Learning Experiences

Teacher Tips Students need to use models from previous

79 I can use a model to relate key features of DNA (antiparallel strands, complementary bases and hydrogen bonding) to the mechanisms of DNA replication. (1, 3b)

80 I can use a model to investigate the process of semi-conservative replication and compare the leading strand to the lagging strand. (3, 4) 81 From that model, I can draw conclusions about errors that occur during replication. (3c)

In the previous section, students focused on the cellular processes that convert the DNA blueprint into the final products associated with a specific trait. The following activities illustrate how these DNA instructions are replicated and passed from parent to offspring, segregating traits across generations in a mathematically predictable manner. Returning to the models used in learning target #60, students identify the structural components of DNA that play a role in replication, with a special emphasis on how the 5’ and 3’ orientation of DNA nucleotides results in the antiparallel nature of DNA. Stu- dents also are reminded of the complementarity nature of nitrogenous bases and how hydrogen bonding holds complementary bases together across the two DNA strands.

Students explore the process of semi-conservative DNA replication using a combination of models, diagrams, animations, and videos. Students demonstrate comprehension through various informal assess- ment methods such as: • creating a cartoon, storyboard, sketch, or role play • manipulating a model of DNA to step through semi-conservative replication Student work should identify and describe the function of molecules required for replication (e.g. single strand binding proteins, helicase, primase, DNA polymerase) and differentiate between replication on the leading and lagging DNA strands. Once students have demonstrated a solid grasp of the replication process, they are challenged to modify their models to explain how deletions, inser- tions, translocation, substitution, inversion, frameshift, and point muta- tions can occur during the process of DNA replication. Students predict the impact of these errors in terms of protein production and/or function.

activities. Models can be made from beads, candy, paper manipulatives, etc. Students can identify parts of the model by labeling the model, making a key or sketching parts on paper.

Teacher Resources

Teacher Tip Students need to use models from previous activities. Models can be made from beads, candy, paper manipulatives, etc.

DNA Replication Basics — Howard Hughes Medical Institute This is a short 3D animation that shows how DNA is replicated at the molecular level. bit.ly/DNA-replication-basics Nuts and bolts of DNA replication — NOVA Students watch an animation to show the mechanisms of DNA replication. Discussion questions are included for students to answer. bit.ly/NOVA-DNA-replication Students can manipulate models to demonstrate semi-conservative replica- tion and be able to explain the process including errors that can occur.

Teacher Resources

Use previously made models to identify the features of DNA mentioned in learning target #80.

Notes:_ _________________________________________________________________________

_______________________________________________________________________________

A Field Guide to the Alabama Standards

The Biology Compendium

Made with FlippingBook - Online magazine maker