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.
Instead of surveying the paper as a whole, you can count sentences within paragraphs. If so, all paragraphs should have between three and ten full sentences. All in all, a strong and coherent paragraph starts and ends itself, and so there's no need to count paragraphs when the argument is clear and directed.