Marita is analyzing the population of various songbirds in her neighborhood. She estimates how the population is increasing by and decreasing by , as different birds enter and leave the area. She thinks that the blue jay population increased by because it doubled over a short time, but then it followed a pattern of when the population approached the .

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