Spiral Structure

question 18

Multiple Choice

Spiral structure

• A) rotates at the same speed as the gas in the disk.
• B) rotates at a speed that is different than the gas in the disk.
• C) stays constant in time as the gas in disk rotates through it.
• D) None of the above is true.

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Definitions:

Adenohypophysis

Portion of the hypophysis derived from the oral ectoderm; also called anterior pituitary.

Parathyroid Glands

The parathyroid glands are small endocrine glands in the neck that produce parathyroid hormone, which regulates calcium levels in the blood.

Somitomeres

Early segmented structures in embryonic development that give rise to somites, precursors to skeletal muscle, vertebrae, and dermis.

Neural Crest Cells

Embryonic cells originating at the border of the neural tube that migrate and differentiate into a diverse range of cell types, including some types of neurons, glial cells, and melanocytes.