In mammals, urine drains out of the ____ into a collecting duct.​

The primary organ where erythropoietin is produced is the

Plasma makes up approximately ____ percent of the total blood volume.​

The ____ are the initial branches of the trachea that lead into each lung.​

Kidneys regulate

Osmoconformers tend to live in environments with variable solute concentrations.

Amphibians often use ____ as a respiratory surface.​

Imagine that you have been assign the task of describing a new mammalian species.  You note that this species has mutated so RBCs no longer go through final stage of maturation.  Predict how this might affect the species.

Many birds, such as seagulls which rarely drink fresh water, deal with the osmotic stress of taking in large quantities of salt in their food mainly by ____.​

Protonephridia are found in ____.​