Almost all of the CO2 we breathe out is made in ? a. photosynthesis
b. the electron transport chain
c. the Krebs cycle

The table below shows the elements that mainly comprise each of the four layers of earth: elements in layers layer main elements crust oxygen, silicon mantle iron, magnesium outer core iron, nickel inner core iron which of these elements make up the layer that is 0.2 to 1.1 percent of earth's total diameter?

Animals have a variety of adaptations, including trachea and gills, which allow this key process to occur. which provides the molecules necessary for cellular respiration and efficient atp synthesis?

Identify the area on the image where the force of attraction is the strongest.