Which of the following best defines the pharynx? an external opening of the body that takes in air a small bone in the wall of the nasal cavity an airway leading from the nose to the trachea an air-filled cavity in the head

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