<h2>Answer </h2>
Lactic acid fermentation ocurrs in muscle cells when oxygen is in low supply
<u>Explanation</u>
The lactic acid fermentation in the muscles cell occurs when muscles work faster and it occurs due to the lack of supply of oxygen in the cell. The lactic acid fermentation is a type of aerobic respiration. The lactic acid formation is due to excessive exercise by individuals and oxygen which is essential for living, is less in the muscle which causes the feeling of burning in the muscles.
The answer is the last one: amoebas, yeasts, hydras, and ferns
The contractile vacuole expels excess fluid from the cell.
Let me try...
How about, grass, moose(moose eats grass), black fly(when moose dies it's eaten by fly), fish(fish can catch flies sometimes), and then Osprey(birds eat fish).
The second one... How about, grass, deer(deer eats grass), then wolf(eats deer), the mosquito(sucks wolf's blood), I don't know the dragon fly though
HOPE THAT HELPED SOMEWHAT :)