Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Note Organic and biochemical equations are frequently written showing only the organic reactants and products. In this way, we focus attention on the organic starting material and product, rather than on balancing complicated equations. Ethanol is oxidized in the liver to acetaldehyde:. Answer: products

A: Organic and biochemical equations show the initial and final products of the equation, respectively known as the reactants and what else?
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Q: Passage: Plasma cells are activated B cells that secrete antibodies. Antibodies are large, Y-shaped proteins that recognize and bind to antigens. Plasma cells are like antibody factories, producing many copies of a single type of antibody. The antibodies travel throughout the body in blood and lymph. Each antibody binds to just one kind of antigen. When it does, it forms an antigen-antibody complex (see Figure below ). The complex flags the antigen-bearing cell for destruction by phagocytosis . Answer: antibodies

A: What do you call large, y-shaped proteins that recognize and bind to antigens?
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Q: Passage: Gravity has traditionally been defined as a force of attraction between things that have mass. According to this conception of gravity, anything that has mass, no matter how small, exerts gravity on other matter. Gravity can act between objects that are not even touching. In fact, gravity can act over very long distances. However, the farther two objects are from each other, the weaker is the force of gravity between them. Less massive objects also have less gravity than more massive objects. Answer: gravity

A:
What is the term for the force of attraction between things that have a mass?
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