Exploring Gel Electrophoresis and Phylogeny

What is the primary purpose of gel electrophoresis in molecular biology?

• To amplify DNA

• To separate molecules based on size and charge

• To synthesize proteins

• To observe cell division

Which component of a phylogenetic tree represents a common ancestor?

• Leaf

• Branch

• Node

• Root hair

Tags

NGSS.HS-LS4-1

What does a cladogram primarily show?

• The chronological order of fossil discoveries

• The evolutionary relationships among species

• The number of chromosomes in a species

• The habitat of organisms

Tags

NGSS.MS-LS4-2

Which molecule is most commonly analyzed using gel electrophoresis?

• Glucose

• DNA

• Lipids

• Cellulose

Which of the following is a difference between a cladogram and a phylogenetic tree?

• Cladograms show evolutionary time, phylogenetic trees do not

• Phylogenetic trees can show branch lengths proportional to evolutionary change, cladograms do not

• Cladograms use DNA evidence, phylogenetic trees do not

• Phylogenetic trees only show extinct species

Given a simple cladogram, how would you determine which species are most closely related?

• By finding species with the most similar names

• By identifying species that share the most recent common node

• By counting the number of branches between species

• By comparing the length of the branches

Tags

NGSS.MS-LS4-2

How can molecular evidence, such as DNA sequences, improve the accuracy of phylogenetic trees compared to using only physical characteristics?

• DNA sequences are easier to observe than physical traits

• DNA sequences provide more objective and quantifiable data

• Physical traits are always misleading

• DNA sequences are not affected by evolution

Tags

NGSS.HS-LS4-1

NGSS.HS-LS4-2

A researcher wants to compare the evolutionary relationships among four species using both a cladogram and a phylogenetic tree. What additional information can the phylogenetic tree provide that the cladogram cannot?

• The order of evolutionary events

• The relative amount of evolutionary change

• The names of the species

• The presence of homologous structures

If two DNA samples produce identical banding patterns after gel electrophoresis, what can be inferred about their genetic relationship?

• They are genetically identical or very similar

• They are unrelated

• They have different numbers of chromosomes

• They are from different species

Tags

NGSS.HS-LS3-1

A student is given a phylogenetic tree and asked to identify the outgroup. What is the best strategy to do this?

• Find the group with the most branches

• Identify the group that diverges earliest from the rest

• Choose the group with the longest name

• Select the group with the most derived traits