Which of the following processes causes most of the carbon dioxide from the blood to move into the alveoli?
A. Passive transport using carrier proteins
B. Active transport using energy
C. Conversion to carbon monoxide
D. Diffusion down a concentration gradient
Most of the carbon dioxide from the blood moves into the alveoli by diffusion down a concentration gradient ¹. Carbon dioxide is always carried in the blood and is released into alveolar air during expiration ¹. Respiratory gases move from higher concentration to lower concentration ¹. In alveolar air, when carbon dioxide is less than in blood, carbon dioxide is released ¹.
The other options are incorrect because they do not accurately describe the process by which most of the carbon dioxide from the blood moves into the alveoli. Passive transport using carrier proteins, active transport using energy, and conversion to carbon monoxide is not the processes responsible for moving most of the carbon dioxide from the blood into the alveoli.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: Which of the following best describes the result of using a catalyst in a chemical reaction?
A. A more desirable product is often formed.
B. The reaction is completed in a shorter amount of time.
C. A greater amount of heat energy is released by the reaction.
D. The yield of product is increased.
Answer Explanation
The result of using a catalyst in a chemical reaction is that the reaction is completed in a shorter amount of time ¹. A catalyst is a chemical substance that affects the rate of a chemical reaction by altering the activation energy required for the reaction to proceed ¹. This process is called catalysis ¹. A catalyst provides an alternative pathway for the reaction, one that has a lower activation energy than the uncatalyzed pathway .
The other options are not correct because they do not accurately describe the result of using a catalyst in a chemical reaction. A more desirable product is not necessarily formed, a greater amount of heat energy is not necessarily released by the reaction, and the yield of product is not necessarily increased as a result of using a catalyst.
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Q #2: Hikers who found a human body at high altitude in the Italian Alps thought the man had died recently, but tests indicated he was shot with an arrow more than 5,300 years ago. Which of the following would be the best reason for prolonged preservation of the body?
A. The ultraviolet rays at such a high altitude caused all his molecules to be preserved.
B. The food that the person ate contained toxins that killed the bacteria that would have otherwise destroyed the body.
C. The body was frozen in the cold temperature of the Alps shortly after he died and remained frozen until it was found.
D. The arrow wound caused blood to flow out of the body which led the enzymes that would break down tissue to be cleared from the body.
Answer Explanation
The best reason for the prolonged preservation of the body is that it was frozen in the cold temperature of the Alps shortly after death and remained frozen until it was found. Freezing can preserve a body by slowing down or stopping the decomposition process.
The other options are not as likely to have caused prolonged preservation.
Ultraviolet rays can damage molecules rather than preserve them. Toxins in food would not necessarily kill all bacteria that could cause decomposition. Blood loss from an arrow wound would not necessarily clear all enzymes that could break down tissue.
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Q #3: Which of the following immune system molecules creates holes in the cell membranes of their target cells in order to destroy the cell?
A. Perforins
B. Interferons
C. Cytokines
D. Lymphotoxins
Answer Explanation
Perforins are immune system molecules that create holes in the cell membranes of their target cells in order to destroy the cell. Perforins are proteins that are released by cytotoxic T cells and natural killer cells
They form pores in the target cell membrane, allowing water and ions to enter the cell and causing it to swell and burst.
The other options are not correct because they do not accurately describe the immune system molecules that create holes in the cell membranes of their target cells. Interferons, cytokines, and lymphotoxins do not create holes in cell membranes.
