In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: This organ produces a tetrapeptide, which bonds to macrophage receptors, and is known as tuftsin. The sinusoids of one portion of this organ contain blood and a reserve of monocytes which can be utilized in the case of hemorrhagic shock. The other major portion of this organ contains Malphigian corpsules and synthesizes antibodies. Located in the abdominal region and consisting of red and white pulp, for 10 points, name this organ part of the lymphatic system that helps to filter and clean the blood.

A: Social Science
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Q: In ferromagnetic materials, a version of this effect occurs in which the resultant resistivity predicted by this effect contains an additional zero-field term proportional to the magnetization. Arranging two solid-state elements which demonstrate this effect at right angles to each other and summing their output voltage to eliminate the noise is a typical way of producing a magnetic field sensor using this effect. This effect is derived by noting that the current crossed with the magnetic field creates a transverse current, which results in a potential difference. For ten points, identify this classical effect in which charge flowing across a transverse magnetic field results in an electric field component orthogonal to both the current and the magnetic field, often used to measure the sign of charge carriers.

A: Science
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Q: This element has a characteristic D line at 589 nanometers and is produced in the electrolytic Castner process. The movement of this element is counteracted by the movement of potassium in a namesake "pump" based off of active transport. A strong base containing hydroxide and this metal is known as lye while baking soda consists of a compound containing this metal and bicarbonate. For 10 points, name this alkali metal found along with chlorine in table salt.

A:
Science
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