When air moves into the lungs, oxygen O is converted into carbon monoxide
O diffuses across the membranes of the alveoli and enters the blood
O diffuses across the membranes of the alveoli and exits the blood
O moves across the membranes of the alveoli by active transport

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.

All eukaryotic cells contain small bodies called

Identify two examples of chemical reactions that you have encountered during the last week. identify an exothermic and endothermic reaction. explain.