An example of mitosis at work is a leaf... turning yellow.
growing.
taking in carbon dioxide.
performing photosynthesis.

Animal bodies (and even plant bodies for that matter) are complex enough that life couldn't exist without enzymes. enzymes are usually large, complex biological catalysts that are expensive to make. enzymes speed up the rate of chemical reactions without being used up during the reaction (they can be reused many times). they are highly specific in the reactions they regulate. knowing what enzymes are and how they function, why does this explain why complex life forms could not exist if there were no enzymes.

The organelle pictured is found in cells of and is theorized to have once been an independent organism.

Gene expression is the activation of a gent that results in a question 1 options: protein dna mitochondria