The Decline in Approximately 70% of the World's Bird Species

question 100

Multiple Choice

The decline in approximately 70% of the world's bird species is particularly alarming to scientists because

• A) This is the first time any bird species have been threatened with declining numbers.
• B) It is not caused by any human activities that scientists can determine.
• C) Only land birds are affected, while water birds seem to be maintaining normal population numbers.
• D) Birds are excellent environmental indicators.
• E) Birdwatching now generates a significant portion of tourist dollars in some countries.

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Definitions:

Connective Tissue

Tissue that supports, binds together, and protects tissues and organs of the body.

Matrix

A substance or environment in which something develops; in biology, it often refers to the intercellular substance of a tissue.

Connective Tissue

Tissue that supports, connects, or separates different types of tissues and organs in the body, including blood, bone, and fat tissues.

Nerve

A bundle of fibers that transmits electrical impulses between the brain and the rest of the body, facilitating communication.