Mass Extinctions

question 67

Multiple Choice

Mass extinctions

• A)remove many species,but they are usually replaced within a million years or less by an even greater diversity of life.
• B)are caused by human activity and did not occur prior to the expansion of the Earth's human population.
• C)remove well- adapted species and groups from the Earth,so that it may take millions of years for species diversity to recover.
• D)mainly serve to "weed out" poorly adapted organisms and make room for new,better adapted species.

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Definitions:

Angiosperms

These are flowering plants, making up the largest group in the plant kingdom, characterized by producing seeds enclosed within a fruit.

Endosperm

Endosperm is the nutritive tissue within seeds of flowering plants, serving to feed the embryo during germination.

Vascular Tissue

The specialized tissue in plants responsible for the transport of water, nutrients, and sugars throughout the organism.

Mosses

Mosses are small, non-vascular plants that typically grow in dense green clumps or mats, often in damp or shady locations.