In the Countercurrent Exchange System of Fish Gills

question 27

Multiple Choice

In the countercurrent exchange system of fish gills,

• A)blood flow in the gills reverses direction with every heartbeat.
• B)blood and water are separated by a thick polysaccharide barrier.
• C)blood and water flow in the same direction.
• D)blood and water flow in opposite directions.

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Definitions:

Australia

A country and continent surrounded by the Indian and Pacific oceans, known for its Sydney Opera House, Great Barrier Reef, and unique wildlife.

Plant Species

Distinct types of plants that share similar characteristics, capable of interbreeding to produce fertile offspring.

Medicinal Properties

Characteristics of substances (often plants, fungi, or animal products) that allow them to be used in treating, curing, or preventing disease and improving health and well-being.

Tropical Forests

Dense forests located in the tropical regions of the world, characterized by high rainfall and biodiversity.