Countercurrent Exchange Is Evident in the Flow of ________

question 29

Multiple Choice

Countercurrent exchange is evident in the flow of ________.

• A) water across the gills of a fish and the blood within those gills
• B) blood in the dorsal vessel of an insect and that of air within its tracheae
• C) air within the primary bronchi of a human and the blood within the pulmonary veins
• D) water across the skin of a frog and the blood flow within the ventricle of its heart

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Definitions:

Cyanobacteria

Photosynthetic microorganisms found in water, sometimes referred to as "blue-green algae," important for their role in nitrogen fixation and oxygen production.

Oxygen-rich Atmosphere

An atmosphere that contains high levels of oxygen, typically associated with the development and sustenance of complex life forms on Earth.

Carbon Dioxide-rich Atmosphere

An atmosphere that contains a high concentration of carbon dioxide, affecting climate and living organisms.

Bird-like Hip

A type of pelvis structure found in some dinosaurs characterized by a forward-tilting pubis, similar to that of birds.