Examine the following figure and answer the following question...

Question

Examine the following figure and answer the following questions.

Phylogenetic tree illustrating shared morphologic characteristics among various animal clades, including vertebrates and primates.

What characteristic is shared by all clades in the figure?

Accepted Answer

Hi, everyone. Welcome back. Let's look at our next question. It says which of the following methods is commonly used to construct a philo genetic tree. Let's recall from a content video, what a Fila genetic tree is. And that is a diagram that shows evolutionary relationships between species specifically where they diverge from common ancestors. And in the past, various trees have been done based on observations of the anatomical structures of different species comparing them to each other. But in modern times, the method that we most commonly used to develop these trees most accurately is choice B D N A sequencing. It determines the nucleotide sequence of a particular D N A region. So knowing this DNA sequence has this application towards creating philo genetic trees because you can use the sequencing to compare regions of DNA and compare genes. You can compare non coding regions between different species. And then the degree of similarity can be used to infer evolutionary relationships and then construct a file a genetic tree. Since we know that DNA mutations are what lead to the changes that natural selection acts upon to cause species evolution. By looking at the D N A and how the DNA from different species differs from each other. We can infer when different species diverged from common ancestors. So D N A sequencing is that method because of this. So let's look at our other answer choices to understand why they're not correct choice. A is DNA profiling. Well, DNA profiling um involves the use of DNA sequencing by looking at DNA samples from different people and looking specifically at regions that tend to vary from individual to individual. So certain regions are um in common like a gene that's the same D N A sequence in all human beings. Um But there are certain regions that have a lot of variability like these single nucleotide polymorphisms from single individual to single individual. And by looking at the sequences of these regions, you can use these DNA sequences to identify individuals and that's called DNA profiling. So, but that's not used to construct a genetic trees that's used to identify individuals from D N A samples. So we're going to cross that out then choice C PCR analysis. PCR analysis we recall is a way to amplify specific DNA sequences from a sample. So if you have a sample with very tiny amounts of DNA, you can use these probes to make large amounts of a particular region of that D N A. So PCR analysis obviously the most common way to create samples for DNA sequencing that might be used to construct a file A genetic tree. But PCR isn't the method to construct the tree. So it's involved in the process but not the answer we're looking for. So choice C is not an answer. And then finally, northern blotting, northern blotting is a technique used to detect R N A sequences in a sample. You have your given sample and you use a complimentary see DNA probe to look for specific RNA sequences. And that can be used for studying gene expression. But again, not a method used to construct a genetic trees. So not our answer. So which of the following methods commonly used to construct a philo genetic tree choice B D N A sequencing? See you in the next video.

Examine the following figure and answer the following questions.

What characteristic is shared by all clades in the figure?

Key Concepts

Clades

Phylogenetic Tree

Shared Characteristics

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