1. increased blood concentration is sense by osmoreceptors in the hypothalamus – this triggers ADH release into the blood, which therefore causes retention of water; this lowers blood concentration and increases blood volume/pressure; ADH increases water permeability of the collecting ducts by stimulating the insertion of aquaporins, or water channels, into the plasma membrane

2. see above; more water is retained and urine volume is down

3. it inhibits release of ADH so that urine volume increases, blood volume decreases, and this can lead to dehydration and headaches

4. it is in the cells in the walls of the arteriole and distal convoluted tubule; see diagram #3

5. the lymph vessels are associated with the blood vascular system and include lymphatic capillaries, larger vessels, and the thoracic duct – the vessel that returns fluid back into the blood vascular system

6. lymph is very similar to blood plasma – water, ions, nutrients, wastes, antigens (anything foreign to the body); it comes from peripheral tissues after blood pressure has pushed water out of the blood to the tissues (I think)

7. return fluid to the blood, produce/maintain lymphocytes (WBCs) to take care of invaders before they spread, and for transport of some nutrients and hormones

8. they are associated with epithelia facing the environment (like the GI tract and respiratory system); they have lots of connective tissue and lymphocytes but are not surrounded by a capsule; the tonsils and appendix have lots of lymphoid nodules and, when infected, can lead to tonsillitis and appendicitis

Our friend, the democratic dentist explains his thoughts on methodologies in dentistry .

The Nissan Frontier is a great vehicle in need of grille guards.

9. spleen, thymus, lymph nodes