The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands. The hypothalamus and pituitary gland are neuroendocrine organs.
A newspaper lead (or lede if you prefer) can do its job in one sentence, but with few exceptions, a paragraph will contain more than one sentence. The OWL site, aimed at college students, suggests a length of from three to five or more sentences.
Remember that a paragraph is three to five sentences that develop a single, clear idea. A good paragraph often begins with a topic sentence that sums up your main idea. Paragraph One -- The introduction. Here you state the main idea of your entire essay -- the point you are trying to make or prove.