Match each cardiac valve with the two chambers it separates. Each pair of chambers may be used more than once, or not at all. tricuspid mitral bicuspid pulmonary semilunar aortic semilunar A. right atrium and right ventricle B. left atrium and left ventricle C. right ventricle and pulmonary artery D. left ventricle and aorta E. right ventricle and aorta F. left ventricle and pulmonary artery

Elements and compounds are pure substances that cannot be broken down physically into a simpler substance. a physical change doesn’t break the bonds between atoms of a substance or form new ones. compounds can be broken down by a chemical change. a chemical change breaks chemical bonds and/or forms new ones between atoms of a substance. what simple substance would a compound break into? the basic elements that make it up! for example, if you passed a very strong electric current through water you’d break the chemical bonds in water and be left with oxygen and hydrogen. which of the following is an example of a chemical change? a separating water into different glasses b breaking frozen ice cubes with a hammer c running an electric current through water d boiling water to evaporate it on a stove

Cassandra made a venn diagram to compare and contrast the two stages of cellular respiration. which belongs in the area marked x? energy is released. oxygen is used up. glucose is broken down. carbon dioxide is used up.

Astudent sees several ants walking up a wall following the exact same trail that an ant took earlier. she wants to apply the scientific method to determine how the ants detected the trail. which of these steps would come first in her application of the scientific method? perform an experiment by cleaning the scent away from part of the trail. draw a conclusion that the ants follow a scent trail. make a prediction about what the ants will do after she cleans away part of the trail. hypothesize that the ants are following a scent trail that the first ant left.