mrs gren

所有生物都有必需的生命迹象，MRS GREN是七个生物必须运动的简称 分别是：
M Movement All living things move,even plants.
R Respiration. Getting energy from food.
S Sensitivity. Detecting changes in the surroundings.
G Growth. All living things grow.
R Reproduction Making living things of the same type.
E Excretion Getting rid of waste.
N Nutrition. Taking in and use food.

原句解释：Living things have certain life processes in common, there are 7 things they need to do to count as being alive.MRS GREN is a funny way to remember them.