Keys at the Phylum (Division) Level May Not Be Completely

question 13

Multiple Choice

Keys at the phylum (division) level may not be completely practical because of which of the following?

• A) They may require chemical tests that are not easily performed.
• B) They nearly always require electron microscopes.
• C) They include so many exceptions that they become cumbersome.
• D) They mainly consist of simple listings of organisms.
• E) None of these answers are correct.

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Definitions:

Sporophyte

The diploid, spore-producing phase in the life cycle of plants that undergo alternation of generations.

Vascular Tissue

Specialized plant tissue consisting of xylem and phloem, responsible for water, nutrient transportation, and structural support.

Protected Zygote

A fertilized egg cell that is safeguarded from the external environment by physical or biochemical means.

Cell Walls

Rigid layers found outside the plasma membrane in plants, fungi, bacteria, and algae cells, providing structure, protection, and support.