Which Pair of Structures Evolved into Modifications That Led to Successful

question 220

Multiple Choice

Which pair of structures evolved into modifications that led to successful movement of gnathostomes from aquatic to terrestrial habitats?

• A) Swim bladder and paired fins
• B) Lungs and cartilaginous skeleton
• C) Paired fins and cartilaginous skeleton
• D) Lungs and swim bladder
• E) Pharyngeal arches and swim bladder

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Definitions:

Summation

The process of adding together excitatory postsynaptic potentials (EPSPs).

Temporal

Relating to time or denoting time as opposed to space.

Spatial Summation

A mechanism in neural communication where multiple presynaptic neurons together stimulate a postsynaptic neuron to threshold, causing it to fire an action potential.

Synaptic Terminal

The end part of an axon that makes a synaptic contact with another neuron or with a muscle or gland cell.