Which nitrogen base replaces thymine (t) in rna? cytosine(c) uracil (u) guanine (g) adenine (a)

Once an egg cell is fertilized by sperm, the cell then, as the embryo develops, it receives nourishment and eliminates wastes by transferring substances from its blood to its mother's blood. a. becomes a fetus immediately and exits the womb b. begins to divide and implants itself in the wall of the uterus c. remains in the uterus without dividing for several months d. travels back to the ovaries until the fetus is developed

How can we use spectral lines of light coming from the superclusters to identify which is receding from earth at the slowest rate.

Fill in the blank with the best word to complete the sentence. white blood cells protect against and aid in blood clotting when injuries are sustained.