Phylogenetic Trees Based on Nucleotide or Amino Acid Sequences Can

question 31

Short Answer

Phylogenetic trees based on nucleotide or amino acid sequences can be constructed using various algorithms. One simple algorithm is based on a matrix of pairwise genetic distances (divergences) calculated after multiple alignment of the sequences. Imagine you have aligned a particular gene from different hominids (humans and the great apes), and have estimated the normalized number of nucleotide substitutions that have occurred in this gene in each pair of organisms since their divergence from their last common ancestor. You have obtained the following distance matrix.



Answer the following question(s) based on this matrix.
-If species A in the distance matrix represents human, indicate which of the other species (B to D) represents chimpanzee, gorilla, and orangutan, respectively. Your answer would be a three-letter string composed of letters B, C, and D only, e.g. DCB.

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Definitions:

Lateralization

The tendency for some neural functions or cognitive processes to be more dominant in one hemisphere of the brain than the other.

Amygdala

A region of the brain involved in experiencing emotions, such as fear and pleasure.

Motor Cortex

A region of the cerebral cortex involved in the planning, control, and execution of voluntary movements.

Frontal Lobes

Regions of the brain located at the front part of the cerebral cortex, involved in decision making, problem-solving, control of purposeful behaviors, consciousness, and emotions.