The correct answer is A. maintaining homeostasis.
Homeostasis is a term referring to an organisms continuous process of maintaining and auto-regulating the conditions of its internal environment. Variables such as pH, temperature, and fluid balance need to be at optimal conditions in order for the organism to function properly.
In this example, the phosphate buffer system permits the organisms to maintain a constant pH in their intracellular fluid. This is one of the organism's homeostatic mechanisms.
Tracheae to distribute oxygen
I recall that Professor Kwang had observed amoebas that had cannibalized bacteria cells. The bacteria were slaughtering the amoebas, but somehow some survived. This particular group of amoebas contained bacteria that thrived inside it. Hence the name, endosymbiosis. However, this lucky group and it's offspring could not survive without bacteria.
<span>Answer: A) Dark moths had a survival disadvantage in industrial Dorset.
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This question can be solely answered using the data you're given! The graph is broken down by place, and then moth type.
In forested Birmingham, the green bar for the light moth is much higher than the orange one for the dark moth. That means the light moth had a survival advantage (eliminating option D) and the dark moths had a survival disadvantage (eliminating option C).
In industrialized Dorset, the green bar for the light moth is much lower than the orange one for the dark moth. That means the light moths were at a survival disadvantage (eliminating option B). The dark moths were are a survival advantage, but option A says "disadvantage," which is clearly wrong! That makes A your answer.
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