The Following Questions Refer to the Description Below

question 36

Multiple Choice

The following questions refer to the description below.
While on an intersession course in tropical ecology, Kris pulls a large, snakelike organism from a burrow (the class was granted a collecting permit) . The 1-m-long organism has smooth skin, which appears to be segmented. It has two tiny eyes that are hard to see because they seem to be covered by skin. Kris brings it back to the lab at the field station, where it is a source of puzzlement to the class. Kris says that it is a giant oligochaete worm; Shaun suggests it is a legless amphibian; Kelly proposes it belongs to a snake species that is purely fossorial (lives in a burrow) .
-Which of these characteristics added most to vertebrate success in relatively dry environments?

• A)the amniotic egg
• B)the ability to maintain a constant body temperature
• C)two pairs of appendages
• D)claws
• E)a four-chambered heart

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Definitions:

Labor

The process of childbirth, beginning with contractions of the uterus and ending with the delivery of the baby.

Epidural

A medical procedure involving the injection of anesthesia into the epidural space of the spinal cord to provide pain relief, particularly during childbirth.

Spinal Canal

The cylindrical space within the spine that houses and protects the spinal cord.

Anesthesia

A medical intervention that results in partial or complete loss of sensation, often used to eliminate pain during surgery.