How Many Different Unrooted Tree Arrangements Are Possible for a Phylogenetic

question 19

Multiple Choice

How many different unrooted tree arrangements are possible for a phylogenetic tree relating five species?

• A) 5
• B) 15
• C) 25
• D) 105

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Definitions:

Forebrain

The anterior part of the brain, responsible for complex behaviors and functions, including thought, emotion, and sensory processing.

Hypothalamus

A region of the brain below the thalamus that coordinates both the autonomic nervous system and the activity of the pituitary, controlling body temperature, thirst, hunger, and other homeostatic systems.

Amygdala

A region of the brain within the temporal lobe, crucial for the processing of emotions, especially fear and pleasure.

Temporal Lobes

Regions of the cerebral cortex below the parietal lobes and in front of the occipital lobes; these regions are important for hearing and for recognizing objects, such as faces.