"ocean currents result from two processes: the wind on the surface of the water and variation in water temperature and density. these ocean currents are convection currents. under the tropical sun, water at the equator warms up. at the frigid poles, seawater cools down and sinks. convection cells are set up with warm water moving along the surface to the poles and deep cold water flowing toward the equator. changes in the density of ocean waters, caused by changes in salinity re also important in the formation of ocean currents. ice formation near the poles leaves salt behind in the remaining water. this denser, more saline water sinks, creating its own density-driven currents. surface winds also set surface currents into motion."

can you pick the statements that accurately describe oceans currents? check all the statements that are true.

'both the wind and solar energy influence ocean currents.'
'warm water flows away from the equator toward the poles.'
'as the salinity of ocean water increases, density decreases.'
'cold water sinks, warm water rises, creating a convection current.'

The tasmanian devil, a marsupial carnivore, is facing extinction due to devil facial tumor disease (dftd) which causes bulging cancerous lumps and lesions to erupt around the face and neck — often causing enough deformation to make seeing or eating difficult. dftd has evolved into a contagious cancer, a trait that is unique among cancers. devil mating behavior involves biting around the head and neck, allowing cells from one individual — especially cells from the crumbly dftd tumors — to be transferred to the wounds or face of a new individual. this marsupial was once found across australia, but sea levels rose, isolating the tasmanian population, while the australian population went extinct. what would be an outcome of genetic isolation that is likely to have impacted the spread of dftd? a) reduced territory puts diseased individuals in greater contact with non-diseased ones. b) inbreeding results in less variation in facial features so the cancer is generally fatal. c) genetic isolation has made it difficult for scientists to develop a vaccine against dftd. d) the lack of genetic variation in the immune system of tasmanian devils minimizes resistance to the disease.

What are some characteristics of a free enterprise economy?

Which of the following best describes the relationship between glucose and complex molecules such as hormones?