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.
Honestly there's no set amount of sentences in a paragraph. Many will argue its about three to five, but honestly it's just when a subject changes. For example you may have a 2-3 sentence paragraph talking about you looking at your face in the bathroom. You then switch to you going to eat breakfast.