Subject Directories Are Indexes Compiled by Editors and Others Who

question 2

True/False

Subject directories are indexes compiled by editors and others who sift through Web sites and compile the most useful links.

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Definitions:

Ectoderm

The outermost of the three primary layers of an embryo that develops into the nervous system, skin, and related structures.

Germ Layer

One of the primary layers of cells (endoderm, mesoderm, ectoderm) in the early embryo that gives rise to all tissues and organs of the organism.

Sense Organs

Specialized structures in organisms that respond to external stimuli such as light, sound, touch, and chemicals, enabling perception.

Ectoderm

The outermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the epidermis, nerve tissue, and neural crest.