The Hypothalamo-Hypophyseal Portal System

question 280

Multiple Choice

The hypothalamo-hypophyseal portal system

• A) carries vasopressin and oxytocin from the hypothalamus to the posterior pituitary for storage.
• B) carries hypophysiotropic hormones from the hypothalamus to the posterior pituitary to control the release of posterior pituitary hormones.
• C) carries hypophysiotropic hormones from the hypothalamus to the anterior pituitary to control the release of anterior pituitary hormones.
• D) carries vasopressin and oxytocin from the hypothalamus to the anterior pituitary to control the release of anterior pituitary hormones.
• E) both (b) and (c) above.

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Definitions:

Hypertonic

A term referring to a solution having an osmotic pressure (or solute concentration) greater than that of the solution with which it is compared. Compare with hypotonic and isotonic.

Osmotic Pressure

The pressure that must be exerted on the hypertonic side of a selectively permeable membrane to prevent diffusion of water (by osmosis) from the side containing pure water.

Turgor Pressure

The force within the cell that pushes the plasma membrane against the cell wall.

Simple Diffusion

The movement of particles from a region of higher concentration to a region of lower concentration without the need for energy input.