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Positive Feedback

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The plasma proteins that bind thyroid hormones are albumin, a prealbumin called thyroxine-binding prealbumin (TBPA), and thyroxine-binding globulin (TBG). The free thyroid hormones in plasma are in equilibrium with the protein-bound thyroid hormones in the tissues. Free thyroid hormones are added to the circulating pool by the thyroid. It is the free thyroid hormones in plasma that are physiologically active (increasing the metabolic rate) and imbalances in these hormones result in thyroid disease. In thyroid storm, a form of hyperthyroidism, the normal body temperature of 37.5 oC may rise to over 40 oC.

Parathormone and the thyroid hormone calcitonin work antagonistically to regulate the plasma calcium and phosphate levels.

Which of the following is an example of positive feedback?

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Process of Oxidation

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Which of the following best describes the process of oxidation?

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Process of Dialysis

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The human kidney can be damaged from a number of causes resulting in a patient’s inability to filter toxins (i.e. urea) from the body which could result in death. Complete kidney failure is usually first treated with dialysis which “cleans” the blood.


Figure 1: The “dialyzer” is a glass container that has 3 main components: (1) blood percolating through to be cleaned; (2) a dividing membrane; and (3) the dialysate. The latter is liquid containing chemicals used to draw fluids and toxins out of the bloodstream and supply electrolytes and other chemicals to the bloodstream (image: kidney.niddk.nih.gov).

All of the following are consistent with the process of dialysis EXCEPT:

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Engulfing Particles into a Cell

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Which of the following terms best describes the process of a cell engulfing solid particles?

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Enzymatic Activity

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If you desire to prevent the initial enzymatic breakdown of polysaccharides, where in the body should the release of such enzymes be blocked?

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Kingdom Monera


Which of the following is considered to be the defining characteristic of organisms in the Kingdom Monera?

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Not Part of the Respiratory System


Which of the following is NOT considered part of the respiratory system?

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DNA Delivery Methods


In gene therapy, which of these non-viral DNA delivery methods requires endocytosis?

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Blood Transfusions


What will happen if a person with AB-negative blood receives a blood transfusion from someone with O-positive blood?

I. Nothing; AB blood is the “universal recipient” and can receive any blood type without eliciting an immune response.
II. Nothing; O-positive blood is the “universal donor”, meaning that any blood type can receive it without eliciting an immune response.
III. The recipient will experience an immune response against the Rh antigen.
IV. The recipient will experience an immune response against the O antigen.

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Beta Oxidation of Fatty Acids


The process of the breakdown of fatty acid molecules (beta oxidation) in mammalian cells takes place in:

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