What are live attenuated vaccines made out of? How do they trigger an immune response?

Which type of respiration takes place when there is no oxygen present

Drag each description to the correct location on the image. not all descriptions will be used. describe the parts of a comet. the frozen part of the comet the atmosphere of gases and dust formed when the nucleus vaporizes tail made of small, solid dust particles tail made of ions that appears to point away from the comet's orbit

Up to what percentage of the world's flora consisted of cycads during the triassic period? 100% 75% 50% 20%