Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: The bottom two chambers of the heart are called the left and right ventricles. The ventricles receive blood from the atria and pump it out of the heart, either to the lungs or to the rest of the body. Answer: ventricles

Answer: What structures receive blood from the atria and pump it out of the heart?

Question: Passage: It was known that DNA is composed of nucleotides , each of which contains a nitrogen-containing base, a five-carbon sugar (deoxyribose), and a phosphate group. In these nucleotides, there is one of the four possible bases: adenine (A), guanine (G), cytosine (C), or thymine (T) ( Figure below ). Adenine and guanine are purine bases, and cytosine and thymine are pyrimidine bases. Answer: nitrogen

Answer: What does the base of a nucleotide within dna consist of?

Question: Passage: Placental mammals give birth to a relatively large and mature fetus. This is possible because they have a placenta to nourish the fetus and protect it from the mother's immune system. This allows for a long period of growth and development before birth. Answer: large

Answer:
Do placental mammals give birth to relatively small or large fetuses?