Alveoli are structures in the respiratory system that allow gas exchange with the circulatory system which type of blood vessel would be most effective in this function?
Veins, because they contain only a tunica externa
O Arteries, because they contain only a tunica externa
O Arterioles, because they contain only a tunica intima
O Capillaries, because they contain only a tunica intima

Which of the following statements is most likely correct about a rock belonging to the jurassic age and a rock belonging to the cambrian age? options: 1) they have identical fossils of organisms that have evolved over time. 2) both have animal fossils preserved in them due to weathering and erosion. 3) they contain different fossils because life on earth has changed through time. 4) the fossils in them were formed on the surface of earth due to exposure to sunlight.

The third stage of cellular respiration is (2 points)

Iwill make you brainliest pleeze answer this fast i have to turn it in really soon brainliest promise easy question 6th grade ! a weather map shows a high pressure system with circles around it. what does this mean? a) an occluded front b) areas of equal altitude c) areas of equal pressure d) a stationary front