Comparing DNA Sequences

Mr. Anderson explains how DNA sequencing has revolutionized biology by allowing us to compare DNA sequences and understand evolutionary relationships. He introduces cladograms as a way to visualize these relationships and provides an exercise to compare DNA sequences. The video also includes a tutorial on using NCBI and BLAST to search for and compare DNA sequences, demonstrating how to find evolutionary significance through these tools.

What has been one of the major revolutions in biology over the last 50 years?

• The invention of the microscope

• The ability to sequence DNA

• The discovery of new animal species

• The classification of plants

What is a cladogram used for?

• To compare protein structures

• To display evolutionary relationships

• To identify genetic mutations

• To measure the speed of DNA sequencing

How can DNA sequences be compared to determine relatedness?

• By counting the number of genes

• By aligning the sequences and identifying differences

• By observing the color of the DNA

• By measuring the physical size of the DNA

Which online tool is used to compare DNA sequences?

• PubMed

• GeneBank

• NCBI BLAST

• Google Scholar

What is the purpose of using the NCBI and BLAST websites in DNA comparison?

• To visualize DNA in 3D

• To compare DNA sequences with a large database

• To create new DNA sequences

• To find the fastest DNA sequencer

What is the role of actin in the human body?

• It is a neurotransmitter

• It is a hormone

• It is a protein found in muscles

• It is a digestive enzyme

What does a 100% match in DNA sequences indicate?

• The sequences have no common ancestor

• The sequences are identical

• The sequences are from different species

• The sequences are completely unrelated

What can be inferred if two DNA sequences are 67% similar?

• They are identical

• They have diverged significantly over time

• They are from the same species

• They have no evolutionary relationship

What is the significance of a distance tree in DNA analysis?

• It shows the physical distance between genes

• It illustrates evolutionary relationships

• It measures the speed of DNA replication

• It identifies the age of DNA samples

What does a lower percentage of DNA similarity suggest about two organisms?

• They belong to the same species

• They have diverged more in their evolutionary paths

• They have a recent common ancestor

• They are more closely related