To test a new drug that has the potential of curing people of the common
cold, a company asked human volunteers who were coughing and sneezing
to participate in a clinical study. the objective of the experiment was to test
whether the new drug could cure the volunteers in the experimental group of
the common cold.

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

Even though the ostrich is a flightless bird, ostriches still possess wings that stretch approximately two meters across when fully extended. scientists speculate that when dinosaurs became extinct, some of the birds that lived during that time became land dwellers since they were able to consume the food that the dinosaurs once ate. over time, these species grew larger and heavier. eventually, the ostrich species became too big to fly. the wings found on ostriches are known as a. analogous structures. b. homologous structures. c. vestigial structures. d. symmetrical structures.

Which areas of earth receive the most precipitation on average? a. tropics b. temperate zones c. regions near 30? n and s latitudes d. polar zones 1