Question 29 (2 points) urine concentration and volume regulation are based on 2 types of countercurrent mechanism: multipler and exchanger. The kidney maintains the body liquid concentration of solutes to 300 mmol/kg. What are the 3 key elements that ensure this this level is kept? O long nephron loops of the Juxtamedulary nephrons reating the gradent, vasa recta preserving the gradient and collecting ducts adjusting osmolalty collecting ducts creating the gradient, vasa recta preserving the gradient and long nephron loops of the purtamedullary nephrons adjusting osmolality O long nephron loops of the juotamedillary nephrons preserving the gradient, vasa recta re-establshing the gradiert and collecting duets adusting osmolalty O long nephron loops the Juxtamedulany nephrons creating the gradient, colecting ducts preserving the gradent and vasa recta adusting oumolalty Question 30 (2 points) sustentacytes were not runctional at puberty for male, what would happen to the newly formed spermatozoa? they would be able to divide by meioss but it would take a much longer time to be synchronous they would die of because of the leck of nutrierts they would not be able to swim they would be an intruder and the immune system weuld destroy them