Hey ur answer should be A and C
I think the correct answer would be A. The yolk sac becomes the placenta. It is membranous sac that is attached to the embryo. It provides all the nutrition and the blood cells needed by the embryo. It is also called the umbilical vesicle.
13 is the answer its so easy
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Answer:
Active transport requires cellular energy for substances to cross the cell membrane; passive transport does not.
Explanation:
Active Transport works against the concentration gradient and therefore needs energy to make it happen
Passive transport such as Diffusion and Osmosis uses the properties of natural movement of particles which moves the molecules from areas of high concentration to areas of low concentration or down the concentration gradient and happens passively without the need for energy
That would be called <span>Defecation.</span>
