Which of the following statements is true of hormones? a. they are secreted exclusively by glands that have ducts. b. they are secreted exclusively by the pituitary gland. c. they are secreted directly into the bloodstream. d. they transmit hereditary traits across generations.

The correct answer is Hormones are secreted directly into the blood stream

Explanation:

Hormones exibit their function by endocrine signaling.At first they are secreted from a gland for Example pituitary gland ,Thyroid gland,adrenal gland directly into the blood stream.Then they are transported via blood to the target cell and bind to the receptor of the target cell thereby activating the later.

      The acivation of receptor molecule generate biochemical signals that stimulates the activity of various enzymes ,growth factor to carry out the biochemical process related to the functioning of the target cell.

the answer is c.) there is a warm front in region a and a stationary front in region b.

blue stars have the highest surface temp

stellar distances are usually expressed in light-years

the measure of a star's brightness is called magnitude

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