In 1900, Dr Lynn Margulis formulated the endosymbiotic theory, which examines the cooperative existence of multiple prokaryotic organisms. What is the significance of such interdependence? A. Itproves that different prokaryotic organisms mated to produce oukaryotic
organisms

B. It provides insight into the now well understood interdependence in food chains and webs

C. It shows that the first prokaryotic organisms lived in large communities

D. It explains how organelles and eventually eukaryotic cells could have arisen

the answer is d.) homologous; have mammary glands

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

for example, no new evidence will demonstrate that the earth does not orbit around the sun (heliocentric theory), or that living things are not made of cells (cell theory), that matter is not composed of atoms, or that the surface of the earth is not divided into solid plates that have moved over geological timescales .