In facilitated diffusion, substances move into or out of cells down their concentration gradient through protein channels in the cell membrane. Simple diffusion and facilitated diffusion are similar in that both involve movement down the concentration gradient.
Answer:
primary
Explanation:
Primary succession occurs when new land is formed or bare rock is exposed, providing a habitat that can be colonized for the first time. For example, primary succession may take place following the eruption of volcanoes, such as those on the Big Island of Hawaii. As lava flows into the ocean, new rock is formed.
Answer:
B. Ethanol
Explanation:
During absence of O2 pyruvic acid is reduced to ethanol in alcoholic fermentation.