How can natural selection lead to speciation over thousands of years?

A17-year-old primigravida is admitted in early labor. her cervix is 2 to 3 cm dilated and 100% effaced. the fetus is cephalic, and the presenting part is at –1 station. her membranes are intact. the patient is holding her boyfriend's hand tightly and breathing rapidly with each contraction. she tells the nurse in a shaky voice, "i'm so nervous. i've never been in a hospital before. i don't know anything about labor or if i can do this." what is an appropriate nursing diagnosis for this patient?

Which of these parts of the membrane large moecules pass through it ?

Which of the following is likely not involved in this example of ecological succession? a) the rotting remains of plants add to the fertility of the soil. b)the soil becomes so fertile that eel grass is replaced by other plant species. c) the roots from plants stabilize the sediment, keeping it in place. d) the concentration of salt becomes so high that all plant life is destroyed.