Which of the Following Was Probably the Least Important Factor

question 10

Multiple Choice

Which of the following was probably the least important factor in bringing about the Cambrian explosion?

• A) the emergence of predator-prey relationships among animals
• B) the accumulation of diverse adaptations, such as shells and different modes of locomotion
• C) the movement of animals onto land
• D) the origin of Hox genes and other genetic changes affecting the regulation of developmental genes
• E) the accumulation of sufficient atmospheric oxygen to support the more active metabolism of mobile animals

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Definitions:

Blood pH

The measure of the acidity or alkalinity of blood, crucial for maintaining essential physiological processes.

Respiratory System

The body system consisting of organs and structures responsible for gas exchange, allowing for inhalation of oxygen and exhalation of carbon dioxide.

Urinary System

The body's drainage system for the eventual removal of urine, comprising of organs such as kidneys, ureters, bladder, and urethra.

Homeostasis

The process by which biological systems maintain a stable internal environment despite changes in external conditions.