The Only Vertebrates in Which Blood Flows Directly from Respiratory

question 31

Multiple Choice

The only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the ________.

• A) amphibians
• B) fishes
• C) mammals
• D) reptiles

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Definitions:

Trailer Service Control Signal

An electronic or pneumatic signal used to control the brakes and other systems on a trailer from the towing vehicle.

Aerodynamic Tractor-Trailer Rigs

Trucks designed with features that reduce air resistance, improving fuel efficiency and reducing operational costs.

Vehicle Braking

Refers to the various systems used to slow down or stop a vehicle.

Tractor-Trailer Semi-Combination Rig

A combination of a tractor unit and one or more trailers attached to it, commonly used for freight transport.