Discussion Topic Heart disease is the leading cause of death among both men and women in the United
States. It is usually caused when a sticky substance called plaque builds up in the
arteries. Often, the only symptoms of heart disease are chest pain or discomfort.
Why do you think heart disease is so prevalent in the United States? How could heart
disease affect other organ systems?

For a to be healthy, it has to have lots of different kinds of plants and animals. all of the different types of plants and animals in an ecosystem. name four types of ecosystems from those listed in the video. b) c) d) most living things live here. all living things depend on how an ecosystem like a game of sticks? why should we build new buildings on existing land? name four extinct species from those listed in the video. b) c) d) the best way to wipe out a species is to the largest ecosystem in the world is this percent of the world is covered by water. how many of all species in the world live in the ocean? list five things you can do to increase biodiversity. b) c) d) e) how many species are we losing per hour?

What are the most explosive events that occur on the sun? umbras solar flares solar winds prominences

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere,b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify,d)anaerobic bacteria kept thriving with more oxygen