In the Oceans on Either Side of the Isthmus of Panama

question 61

Multiple Choice

In the oceans on either side of the Isthmus of Panama are 30 species of snapping shrimp; some are shallow-water species, others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago. The oceans were completely separated by the isthmus about 3 million years ago.
In the figure, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B) . The seawater on either side of the isthmus is separated into five depth habitats (1-5) , with 1 being the shallowest.

The Panama Canal was completed in 1914, and its depth is about 50 feet. After 1914, snapping shrimp species from which habitats should be most likely to form hybrids as the result of the canal?

• A) A5 and B5
• B) A3 and B3
• C) A1 and B1
• D) A1-A3 and B1-B3 have equal likelihoods of harboring snapping shrimp species that can hybridize.

Recognize the leading global contributors to carbon dioxide emissions.

Grasp the nature and impact of the global media environment today.

Analyze the threats posed by megacorporations to national governments.

Understand the factors contributing to hunger, poverty, and the role of cash crops in developing countries.

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Definitions:

SA Node

Sinoatrial node, the heart’s natural pacemaker, located in the right atrium, responsible for setting the rate of heart beats by sending out electrical impulses.

Asystole

A state of no cardiac electrical activity, leading to a lack of contraction of the heart and cessation of blood flow; essentially, cardiac arrest.

Pacemaker

An electronic device that is implanted in the body to regulate the heartbeat by delivering electrical impulses to the heart muscle.

AV Node

The Atrioventricular Node, a part of the cardiac conduction system that delays the transmission of electrical impulses from the atria to the ventricles.