Logical Reasoning

PT131 · S3 · Q3 Hemoglobin, a substance

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Hemoglobin, a substance in human blood, transports oxygen from the lungs to the rest of the body.

Given

Hemoglobin, a substance in human blood, transports oxygen from the lungs to the rest of the body.

With each oxygen molecule it picks up, a hemoglobin molecule becomes more effective at picking up additional oxygen molecules until its maximum capacity of four oxygen molecules is reached.

Grabbing an oxygen molecule changes the shape of the hemoglobin molecule, each time causing it literally to open itself to receive more oxygen.

3.

Which one of the following is most strongly supported by the information above?

  1. A hemoglobin molecule that has

    Too Strong

    A hemoglobin molecule that has picked up three oxygen molecules will be more effective at picking up another oxygen molecule than one that has only picked up one or two oxygen molecules. But being more effective at picking up another oxygen molecule does not make it likely that one will pick up another oxygen molecule. This is similar to the difference between a plurality of votes and a majority of votes. Someone who has received more votes than anyone else has not necessarily received a majority of votes.

    6% picked this

  2. The only factor determining how

    Too Strong

    It’s given that the shape of a hemoglobin molecule is a factor determining how effective a hemoglobin molecule is at picking up oxygen molecules, but that does not mean that it is the only factor.

    1% picked this

  3. Correct

    A hemoglobin molecule that has

    Why this is right

    This is supported by the second statement.

    Skill tested: Most Supported · how this choice captures the argument's function is the move to repeat next time.

    87% picked this

  4. A hemoglobin molecule that has

    Contradiction

    It’s given that grabbing an oxygen molecule changes the shape of the hemoglobin molecule.

    1% picked this

  5. Each hemoglobin molecule in human

    Too Strong

    While it is known that hemoglobin plays the role of transporting oxygen, the statements do not indicate that the only role of hemoglobin is oxygen transport. It turns out that some hemoglobin does not carry any oxygen and instead serves as an antioxidant and regulator of iron metabolism (source: Wikipedia). While you’re not expected to know this, it is important to see that the statement explains a function of hemoglobin, but not suggest that this is the only function of hemoglobin.

    6% picked this

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